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The Top 4 Reasons People Cheat on Their Partners

2. Too many opportunities to encounter attractive others.

Key points

  • Cravings for excitement, danger, and uncertainty can make it hard to resist an adrenaline-boosting fling.
  • Modern culture gives us plenty of opportunities to meet people we may fall for.
  • Infidelity can sometimes be a sign that there is a problem with your relationship.
  • Being unfaithful sometimes just happens but most types of infidelity are committed intentionally.

There is (almost) nothing worse than discovering that your partner has cheated on you. A good romantic relationship builds on mutual trust, respect, admiration, and attraction.

When a loved one commits an act of infidelity, the bond of trust has been broken. You probably no longer feel respected or admired. Worst of all, you may no longer feel that your significant other is attracted to you.

Despite these potentially devastating consequences, we often cheat on our partners. Surveys suggest that more than 60 percent of people have cheated on their long-term romantic partner or spouse at least once (Brogaard, 2015, ch. 8).

Why are so many of us unfaithful? Here are the top four reasons:

We cheat because we crave excitement and unpredictability.

Most of us think that the "honeymoon phase" of relationships is what romantic love is supposed to be like all the time. We fail to see that the early stages of romantic relationships are not what healthy romantic love is like.

These stages of romantic relationships resemble the chemical profile of psychological disorders like generalized anxiety disorder (GAD) and obsessive-compulsive disorder (OCD) (Brogaard, 2015, ch. 2). Like GAD and OCD, the early stages of romantic love are characterized by low brain levels of the neurotransmitter serotonin and high levels of the neurotransmitter dopamine.

Serotonin is correlated with well-being, satiation, and certainty. So, low levels of this brain chemical can elicit feelings of unpredictability and butterflies. Dopamine is associated with extreme pleasure and high levels of motivation. So, high levels of dopamine can induce feelings of ecstasy and energy.

Because the honeymoon phase of romantic relationships often generates low brain levels of serotonin and high levels of dopamine, this phase often induces feelings of extreme pleasure and high energy, combined with feelings of unpredictability and uncertainty. Although this emotional cocktail reflects an unhealthy brain state, it can be addictive.

Once the ecstasy, excitement, and unpredictability of the honeymoon phase of our romantic relationship are gone, we may crave these emotions. Their absence can make it seem like something is wrong with the relationship.

Even though relationships may be more healthy after some time has passed, the lack of constant ecstasy and unpredictability can cause us to believe that our love for the other person has ended.

Cheating is secretive and potentially dangerous, and it can feel exciting and give us a boost of adrenaline. Owing to these attributes, an act of infidelity can give us a fix of the addictive love ingredients we feel are lacking in our long-term romantic relationship.

It is easier than ever to meet people we may get attracted to.

Another reason we cheat is because we can. Prior to the early 1970s, it was far more common for women to be stay-at-home moms and men breadwinners.

These oppressive social structures provided women with very few opportunities to cheat. While men were less restricted, most would have been less likely to meet "eligible" people to cheat with—without intentionally seeking them out.

Back then, it was also typically more difficult to hide a romantic fling or love affair from a long-term romantic partner. With less time away from each other, and no cell phone or internet, most people would need to be quite determined to sustain a romantic love affair—although brief flings perhaps were more common.

Today, we commonly spend significant stretches of time apart from our romantic partners. Most of us work outside the home, and many of us travel for work. We furthermore often go out without our significant others, and we each have our own independent circles of friends. Even when we are together with our partner, other people are only a text message away.

Setting aside the temporary limitations that were (or still are) imposed by the COVID-19 pandemic, modern culture thus gives us plenty of opportunities to meet people we may get attracted to while also making it relatively easy to hide a romantic fling or love affair.

Cheating can signal that something is wrong.

Sometimes infidelity is a sign that something is wrong in your long-term relationship (Brogaard, 2020, ch. 2).

If you and your significant other stay together merely for economic reasons, for the sake of the children, because of shared possessions, or out of convenience, you may end up resenting each other.

If you are unhappy in your romantic relationship, you may be more likely to seek intimacy, admiration, satisfaction, and respect elsewhere.

Occasionally cheating just sort of happens.

Occasionally, cheating can be something that just sort of happens. At a company holiday party, you may get rather tipsy and suddenly find yourself kissing your co-worker in the hallway without ever intending to do it.

While all cheating betrays our partner's trust, an unintended kiss in a hallway after one too many glasses of spiced wine can be relatively innocent.

If, however, you and your co-worker end up going home together or carrying on after the party, that is far from innocent. Unlike a single, quick kiss that just sort of happened, voluntarily going to someone's house requires making an intentional decision to do so.

The same goes for repeat offenses. If you keep finding yourself kissing co-workers in hallways at company parties, you are probably intentionally doing it, even if you are not fully aware of the "intent" at the time.

Facebook image: Vadym_Hunko/Shutterstock


Brogaard, B. (2015). On Romantic Love. Oxford University Press.

Brogaard, B. (2020). Hatred: Understanding Our Most Dangerous Emotion. Oxford University Press.

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