In day-to-day life, there are two kinds of selfishness. One is where you don’t give a damn about anyone else and what they need or want, and just go after what you want, whenever it feels good to do so. This is the kind of selfishness that gives the word a bad rep. The second is just about prioritising our own needs, and articulating them.

We’ve misunderstood the value of selfishness. That isn’t terribly surprising, given that most major religions have always framed it as a vice, with kindness almost always presented as an unequivocal good. But overemphasising the primacy of kindness can make us feel as if we can never put ourselves first, even when we really need to. Kindness is one of the oils that keeps society moving. But it’s not a cost-free behaviour to demand of other people, or of ourselves. You – we, I – get to be top of the pile every now and then.

We can’t only be selfish – that would end badly – but never putting ourselves first is almost as bad. Not saying what we want or need means we never get what we want or need, and in the worst cases we build up a simmering cauldron of resentment, ready to boil over at the least appropriate moment. (Not that I’m talking from experience … ) We think we are being selfless – and we are trying to be good – but actually we are draining ourselves to the dregs. At some point, we end up with nothing left to give – and the result is that we scream at our families or burn out at work.

In fact, being what the humanistic psychologist Scott Barry Kaufman calls “healthy selfish” – as distinct from “unhealthy selfish” – is really good for us. Healthy selfishness comes from a place of self-love where we prioritise ourselves. Kaufman created the Healthy Selfishness Scale as a way to measure the degree to which an individual practises this – and it reads like rules for a life well lived.

To be able to say no in a way that doesn’t cause offence, but also to be content if it does – if you can crack that, you have a skill for life

On the scale are having healthy boundaries and self-respect, and not letting others take advantage of us; self care; having a positive form of selfishness (like exercise) which doesn’t hurt others; giving ourselves permission to enjoy ourselves even if it doesn’t directly help others; and prioritising our personal projects over the demands of others.

When Kaufman studied what life looks like for people of whom some, or all, of these statements were true, he found that they strongly predicted wellbeing, life satisfaction and psychological adaptability, as well as making depression much less likely. People who were more healthily selfish were self-compassionate and felt pride in their achievements, and they also felt less inclined, as he puts it, “to aggressively dominate others”. They were also more likely to help other people even when there was no obvious personal or social gain.

The Dalai Lama has called this wise selfishness, a kind of enlightened self-interest that sees the personal benefits in helping others, although not to the extent that your own needs are sublimated. As the podcaster and happiness writer Dan Harris puts it: “Warmth and compassion are omnidirectional.”

There are blurred lines between what we think of as selfishness, self-centredness, selflessness and altruism. They’re not in opposition; they sit on a continuum. Being selfish enough to take care of yourself shades into a version of altruism if it means you can take care of others down the line, just as being selfless in the most visible way possible – like loudly announcing the trouble you’ve taken over a family lunch – is a kind of self-centredness.

But how do you do it? For many groups – especially for women and people in marginalised communities – healthy selfishness doesn’t come easily. Parents in the global north take a child-first approach to raising their kids in a way no other parents in history have. Our expectations have only grown higher while, at the same time, more and more parents have entered the workforce, according to the Office for National Statistics.

Research by the Economist suggests women also spend more than double the time with their children each day than mothers did 50 years ago; dad time has quadrupled – but the baseline was only 16 minutes. In 1975, only half of working-age mothers were employed. It’s essentially impossible to run a family as though one parent is at home all the time when, in all likelihood, neither parent (if there are two parents to start with) is home much of the time at all. This is an argument for better working practices, shorter working hours and subsidised childcare, not for women to leave the workforce. When you are stretched this thin, it’s hard to ask for – and sometimes to even know – what you need.

We also live in such a doingculture that it’s difficult for many of us to see how intrinsically good it is to look after ourselves because the benefits are not always immediate, visible or part of the production economy. Ours is a culture that really only celebrates constructive rest – the kind that involves spending money, like getting a massage or buying expensive skincare, or which has the aim of having a great idea for that project while you’re out for a walk.

Research in 2021 by Selin Malkoc at The Ohio State University examined the degree to which viewing leisure time as wasteful influences how much we enjoy that leisure (less), and how stressed and liable to anxiety and low mood we then are (more).

Healthy selfishness often starts with a single word: no. But setting boundaries is a skill most of us didn’t learn – or perhaps see modelled – in childhood. “People need to be able to develop the ability to just say no,” says Ammanda Major, a senior sex and relationships therapist at Relate. “Why people struggle with this is interesting. Often, it’s because of our upbringing. As we grow up in families, we get assigned roles. We don’t know we’ve accepted a role, but we have – maybe you’ve grown up being the person who does everything for everybody else, or maybe you’ve grown up being the person who’s expected to shield everybody else from other things. So, understanding how you grew up is the first practical step in working out why you find it difficult [to set boundaries]. Am I scared of not being liked? Am I worried that I’ll offend someone? Am I worried they’ll think I don’t love them? Am I worried that the school think I’m a terrible parent?”

While trying to get everything right, or please everyone all of the time, “we forget where our own margins are, and before we know it we’ve overextended ourselves, and then we’re angry and resentful about it,” says Major. “To be able to say no in a way that doesn’t cause offence, but also to be content if it does cause offence – if you can crack that, then you have a skill for life which will serve you very well.”

When people put their own needs first, everybody around them has a tendency to be happier

Learning to set boundaries starts – like all skills – with practice. “It may feel counterintuitive the first time you do it,” says Major. “The other thing to bear in mind is if people are suddenly experiencing you as different, it is likely that they will have to be different too. So you have to get used to that as well. If one of your reasons for always saying yes is because you love that frisson of somebody being pleased with you, or being given lots of praise, you may have to do without that and how that feels.”

On the other hand, making sure that at least some of your needs are met can benefit the people around you, says clinical psychologist Dr Marianne Trent, host of the Aspiring Psychologist podcast. “We need to remember that we are our own main character,” she says. “Of course there’s give and take, but with the people I work with, what I see is that when they put their own needs first, everybody else around them has a tendency to be happier, more content, and for the systems around them to thrive.”

Putting ourselves first can feel uncomfortably like selfishness as it is traditionally understood, whether it involves radical change like leaving a job or relationship, or moving overseas, or wanting to go away on your own for a weekend. But it’s time we reclaimed selfishness. It’s not bad to want things to be different. It’s OK to decide to be the prime mover in our own lives.

This is an edited extract from Be Bad, Better by Rebecca Seal, published by Souvenir Press at £14.99. To support the Guardian and Observer, order your copy at guardianbookshop.com. Delivery charges may apply.

How to be healthily selfish when …

… your ex wants to stay friends

“It can be difficult to reassert boundaries in relationships, but it’s OK to not meet other people’s needs, and you’re allowed to grieve for a relationship that you think is no longer in your or their best interests,” says psychologist Dr Marianne Trent. By trying to stay friends, “you’re prolonging the healing period and prolonging the distress”.

It’s not just your distress, adds Relate therapist, Ammanda Major: “You may be doing them a huge disservice and not helping them to move on, too. If you have children together, you will always be parents, and you have to prioritise the welfare of the children,” she says. “No matter how difficult, try to keep the channels of communication open about the needs of the children. Over and above that, you don’t need to do anything at all.”

… your kids’ school asks too much of you

Any parent in a class WhatsApp group, or who has signed up to a school’s comms app, will know that, however well intended, the pressure to remember Odd Socks days, meal payments, performance times and tombola donations can feel like a lot.

“One issue with this is that if every other parent around you is saying, ‘Oh, yes, more events, more school trips,’ it can feel isolating if what you’re feeling is, ‘I’m working two jobs, I haven’t got time to make a bunny costume,’” says Major. “Be clear with the school. Say: ‘I want to be as helpful as I possibly can, and this is what I feel able to contribute. Let me know what you want me to do within that parameter.’ You’re demonstrating a willingness to help and you’re acknowledging that you’re part of a community. But you’re also saying: ‘This is what I can offer, and no more.’”

For me, self-reflection has also been vital: I needed to take account of all the messaging I’ve absorbed about what being a “good” parent looks like. This ranges from the cocktail of social media algorithms filling my feeds with calm – and unreasonably attractive – parents and their charming children, to the “gentle parenting” books I consumed when I was night-feeding my children, and what I was trying to prove about my own worth via the medium of handmade World Book day costumes. Once I realised how much of the weight of expectation was internal, I was able to shrug a lot of it off.

… you realise you’ve become the office organiser

If having to plan all the social events for your office, friends or family has crept up on you, what can you do? Pre-empt says Major. “Well in advance, you need to say: ‘It’s September, and I know I normally do the office Christmas party – or the annual friends get-together, or whatever – but this year I’ve got too many commitments already and so I’m handing over to somebody else.’”

This is, of course, more complicated if you’re dealing with a boss who seems to be forcing you into a role that is outside your job description. “If it’s always you who is asked to get the birthday cakes, whereas your 15 male colleagues are never asked, that can be a bullying in the workplace issue or a gender issue,” says Major. “If we’re to break that cycle, we need to invite people who are dishing out that sort of prejudice to reflect on their behaviour. We also have to empower people to feel able to speak up. But it’s a difficult balance because in some contexts you may feel that speaking up could put your job at risk.”In which case, it may be wiser to get advice from someone trustworthy in HR, or to ask a mentor or senior colleague to help you manage the situation more subtly, rather than saying a flat-out no next time you’re asked to arrange a leaving do.

… you don’t feel like having sex

If life feels too stressful to prioritise sex, it’s OK if it falls off the agenda for a bit, says Major. Perhaps you’re exhausted. Perhaps you feel like you’re only just surviving. Perhaps you’ve spent the day with little kids clambering all over you and the last thing you want is yet another body in your personal space. “Your feelings are your feelings and your desires are your desires. We all have the right to say no, thank you. One of the biggest downers for sex and intimacy is stress.”

We hear a lot about how important sex is, especially in long-term relationships, but it’s common andnormal for most couples to go through phases where sex feels less alluring to one or both partners.

“Sometimes that drive just isn’t the biggest thing,” says Major. “It’s all very well saying, ‘Why don’t we go upstairs for a couple of hours?’ But what if you’ve got a three-year-old who’s just thrown up, or you’re about to lose your job? If you share a bed, or have any form of touch – not sensual, not sexual, just touch – that can often be a real connector on which to build. It doesn’t even have to be touch: it can be things like someone caring enough to ask about your day, or how did the hospital appointment go, or the meeting with the teacher; such little things, but goodness me, they can make the biggest difference.”

… a friend starts expecting a lot more from you

When I was in sixth form, I had an older (cooler) friend who lived in university halls, where it was all too easy for me to drop in at random. This slowly drove her mad, and finally she had to tell me to stop it, even though my feelings were a little hurt. “This is about being active in our relationships, rather than letting them be passive processes that wash over us,” says Trent.

There is usually a reason for a friend’s new neediness. “It may be that things are wobbly in their relationship or their job,” she says. Major advocates coming from a place of gentle curiosity, rather than irritation, at least the first time you raise it.

“What has changed for them? Are they feeling vulnerable, and needing more of the reassurance we get from a close friend? You have every right to say I love talking with you, but could we agree when you are going to come around?” You’re also allowed to outgrow a friendship, especially if it feels stifling, one-sided or draining, says Trent. “Take stock and consider whether it’s still working for you. You can end friendships just like you can end a relationship.”