When psychologists encourage this practice, they don’t mean controlling other people with ultimatums or insulating yourself from relationship problems. Instead, setting a boundary involves regulating your behaviour with rules that you set for yourself.

For instance, asking a teen to stop speaking to you disrespectfully isn’t a boundary — it’s a request. But saying “I want to have a conversation with you, but I will not continue to talk with someone who is berating me” is an example of setting a limit.

When we set personal boundaries, we are drawing a line between our needs and those of other people. That helps us maintain healthy relationships, says Catherine A Sanderson, a professor of psychology at Amherst College.

Ignoring those needs can cause us to “explode” emotionally, Sanderson says. And that’s because we didn’t reflect on what we needed in the relationship, she says.

If a partner gives you ‘the ick’, put it in context

“The ick” is a sudden aversion, usually prompted by someone’s behaviour, appearance or personality trait. You can experience it while dating, but it occurs in long-term relationships, too.

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When we’re turned off by something, it isn’t an automatic sign that “there’s something wrong with us or wrong with the other person”, says Kesia Constantine, an adjunct clinical supervisor in applied psychology at New York University.

So if an “ick” crops up in an otherwise healthy relationship, consider whether you can build a tolerance for it, she says. If a person puts tomato sauce on their eggs, for instance, you can avert your eyes.

And as awkward as it may be, consider talking to the person about your reaction, says Isabelle Morley, a clinical psychologist and author of They’re Not Gaslighting You. Because, she says, “that’s a lot of what relationships require — communication and flexibility and adjustments”.

Embrace the power of a script

It might feel corny, but having a few phrases in your back pocket can help foster better communication with your partner, especially when you’re feeling particularly stressed or feisty.

“You start” are two powerful words that couples can say to each other, says James Cordova, a professor of psychology at Clark University and author of The Mindful Path to Intimacy. When couples fight, they are often struggling to be heard at exactly the same moment, he says — like two fire hoses pointed at each other.

Another banger? “Let me try that again.” Laurie Santos, a psychology professor at Yale and host of The Happiness Lab podcast, suggests using the phrase — and shes does so herself — when things come out too harsh.

It’s not that happy couples never fight, she says; it’s that they tend to be good at repair. “Let me try that again” is an easy, effective restart.

Tell your partner what you really want

Obvious? Sure. But Terry Real, a couples therapist and author of Us: Getting Past You and Me to Build a More Loving Relationship, says the No.1 mistake couples make when fighting is failing to clearly articulate what they want. Instead, they tend to complain about the same things over and over, which can drive partners apart.

Don’t confuse asking and whining, Real says.

For instance, complaining about how distant your partner is won’t evoke a generous response, he says, because nagging isn’t a vulnerable act. Having the courage to say what you genuinely want is, he says. You’re much more likely to get a compassionate response if you say something like, “I would really like to find more ways to simply hang out together.”

Never stop playing

When you have been with your partner for years, it’s easy to get bogged down in all of the logistics: paying bills, shuttling kids around, taking care of ageing parents — the list goes on.

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Playfulness can be difficult to muster. But laughter is so important, especially when couples are feeling rundown or overwhelmed, says Stephen Mitchell, a psychotherapist in Denver and a co-author of Too Tired to Fight.

“People underestimate the power of humour in terms of helping couples feel connected and helping them work through challenging moments,” he says. The happiest couples he knows tend to be the ones who find ways to have fun together.

If the organic playfulness that marked your early days feels out of reach, that’s OK. Look for small ways to inject your partnership with a dash of humour. Send a silly text. Turn an everyday task, like a trip to the supermarket, into a game. (Whoever checks all of the items off their list first wins.)

This article originally appeared in The New York Times.

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