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What counts as cheating? It’s a question best answered by you and your partner, as you decide together what your rules and boundaries are. Monogamous, monogamish, polyamorous — there are many ways to be happily committed.

There are also, it seems, many ways to cheat. Last week, my Twitter feed was flooded with articles on so-called “micro-cheating,” minor activities that stop well short of having sex with someone else, but that supposedly constitute infidelity in their own right because they involve temporarily focusing your attention — whether it’s physical or emotional — on someone other than your partner. As I perused these articles, I found that many of them conflated perfectly normal, harmless behaviors (like fantasizing about someone else) with shadier stuff (like purposefully saving the phone number of somebody attractive under a code name in order to avoid detection). As someone who studies sex and relationships for a living, I was annoyed, to say the least.

At first, I was tempted to ignore micro-cheating, and to dismiss it as yet another fleeting internet trend. But I found that I just couldn’t let it go. The concept points to some commonly held beliefs that far too many Americans have about the loves of their lives, beliefs that could cause them unnecessary heartache in the long run.

The truth is that many of the behaviors deemed “micro-cheating” — like checking someone else out — are far from reliable signs of relationship problems. But the fact that they’re categorized as “cheating” reveals an implied demand that our partners never pay attention to anyone but us. Ever. That kind of possessiveness represents an unhealthy and unrealistic approach to love. The hard truth is that it’s very, very difficult for a single person to meet all of your sexual and emotional needs forever.

It reveals an implied demand that our partners never pay attention to anyone but us. Ever.

Humans are not “wired” to find one — and only one — person attractive for their entire lives. This is because we — like many animal species — are subject to something known as the Coolidge Effect. This refers to the well-documented finding that sexual interest in one partner tends to wane over time, but comes roaring back in response to new partners. (In case you’re wondering, this effect is named after a story about former president Calvin Coolidge who, on a visit to a chicken farm, noted the seemingly endless prowess of a rooster that had access to multiple hens.)

Studies have found that both men and women show some degree of habituation — a lessening of sexual interest — when they watch the same porn clip over and over. Likewise, other research has found that when heterosexual men watch porn featuring the same woman every day for a week, they subsequently ejaculate faster when they’re shown erotic images of a new woman.

What these data tell us is that it’s simply part of our nature to be turned on by novelty, which is why most of us fantasize about people other than our partners and find ourselves gazing at attractive strangers from time to time. These things don’t necessarily mean that we no longer love our partners or that our relationships are on the verge of crumbling — more often than not, they’re just part of being human. To deny this and instead chalk these things up to “micro-cheating” is a recipe for relationship disaster. If you insist that your partner should never find anyone but you attractive — a pretty unrealistic expectation, according to science (not to mention common sense) — you’re probably going to have a rough go of it, because every lingering glance they give and emoji they send will become a cause for contention.

To be clear, the fact that the Coolidge Effect exists does not mean that long-term passion is impossible in a monogamous relationship or that an open relationship is the only option. Lifelong monogamy and sexual passion are not mutually exclusive; however, if you want both, you have to work at it by regularly finding ways of introducing novelty into your sex life. For example, research finds that the more acts of novelty and variety couples engage in (like watching porn together, or giving each other massages), the better able they are to keep the flames of passion burning.

It’s natural to find people other than your partner attractive. And this, in and of itself, is not cheating. It’s just how our brains work. And while it may be tempting to see this as an inherent threat to our relationships, there’s a more productive way you can use this insight: working to ensure that novelty remains a big part of your own sex life. This will likely enhance your relationship in the long run.

It’s also natural for us to seek out intimate, emotional connections with people other than our romantic partners. This is why many other so-called micro-cheating behaviors shouldn’t necessarily be viewed as infidelity, either, like confiding in or asking advice from someone who isn’t a romantic partner. We’ve all heard that our spouse should be our best friend, but being too close might not be the best idea.

As therapist Esther Perel eloquently argues in her book Mating in Captivity, when we get so close to a partner — when we’ve effectively merged together — it stifles feelings of autonomy and freedom, while simultaneously eliminating any sense of mystery about the other person. That’s unfortunate, because a little bit of mystery or elusiveness is an essential component of sexual desire. Having some psychological distance or separation can therefore be a very healthy thing, because it gives us the ability to be ourselves while also making us crave our partners. As Perel writes, “Instead of always striving for closeness … couples may be better off cultivating their separate selves.”

It’s okay if your partner doesn’t share everything with you, and we shouldn’t automatically think of that as a form of cheating. In truth, giving each other some space may be good for both of you.

With all of that said, I’m not dismissing all of the behaviors that have recently been categorized as micro-cheating. Some of them are indeed signs of trouble, namely the ones that involve deception. For example, purposefully not telling your friends and colleagues about your relationship so that they think you’re single, or telling your partner that you’re going out for dinner or drinks to discuss work when no work is actually going to take place. This should go without saying, but hiding your relationship status and lying to your partner are the kinds of things that don’t bode well for the future.

Even so: It’s worth keeping in mind that the key to a healthy relationship isn’t being controlling, demanding, and possessive. Instead, you’d be better served by communicating early and often about your rules and boundaries, while also giving each other room to breathe and be yourselves.

Justin Lehmiller, Ph.D.. is the director of the social psychology program at Ball State University and a faculty affiliate of the Kinsey Institute.