Data point to the real reason married people cheat, and you may be surprised

Have you ever felt an unnerving need, nibbling at your brain, to look through your partner’s phone? You can’t quite put your finger on it, but something just feels off.

Infidelity occurs in about 25 percent of marriages over the course of a lifetime. And that includes only extra-marital sex, not just kisses, flirtations or emotional affairs. So, if you want to give your best guess, some form of serious infidelity probably affects at least significantly more marriages than that.

Historically men have cheated at a rate about twice that of women. But the amount of cheating has increased dramatically over the last 30 years. Is that because of the internet? Many believe that easy access to so many people on social media, a smorgasbord of sexual interest, is the culprit, but actually there is a very different story playing out.

Cheating by women has increased by 40 percent over the last 35 years, even as cheating by men has stayed precisely the same, so women are driving this increase in infidelity. Why? Potentially, it's the shift in gender roles and societal norms.

Think about the show "Mad Men" — the guys cheated all the time, and it was considered socially acceptable. The women? Not so much. Even if women were cheating before, they weren’t owning up to it and, in fact, would have been actively hiding it, whereas now some women even wear it as a badge of honor — not a healthy thing at all.

So what does this mean? It means that cheating is up across the board. Divorce is skyrocketing, and the number of unhappy people in long-term committed relationships is higher than ever.

Use of social media has drastically increased emotional cheating and the ability to connect outside of work with colleagues, so much so that it is responsible for a 60 percent increase in affairs. Over 90 percent of women admit to emotional infidelity and 85 percent of men over the course of a lifetime, a staggering number.

So why? What is the reason behind this ultimate act of betrayal? The statistics are starting to show very different reasons than much of the psychology community used to believe.

Shockingly, 56 percent of the married individuals who cheat say that they have a "happy marriage" according to new studies on the topic. How is that possible, you might be thinking? It is these individuals who cheat without a serious emotional connection. Their stated reason for their infidelity was sex and a level of romanticism without an emotional response.

This suggests a slightly different explanation for cheating — a need for desire, not just sex or not even necessarily an emotional interest, but rather that excitement that comes with a first crush, a physical attachment and the initial dopamine surge associated with new relationships. New research shows that these individuals still say they love their partners and have no desire to leave them, but they feel a total loss of intimacy, emotional connection and desire in their marriages.

What’s the solution to that? Let's say you want to continue your relationship, even though your partner has cheated. Modern psychology and therapy, based on these statistics, now suggests that the solution is to re-create desire, not just sex, in your marriage. That adds a slight nuance to advice that has been given for so long by so much of the therapy community.

The statistics show that the need that isn’t being met and that has led to this type of infidelity is a need for desire and connection, and to be in the first throes of dating again and re-building one's relationship essentially from scratch.

Unfortunately, even if a relationship broken by cheating can be rebuilt, its chances of success are slim. The old adage, “once a cheater, always a cheater,” rings true, as those who have cheated before are four times more likely to cheat again.

It evokes the old adage, "When a man marries his mistress, he creates a vacancy." Except that it's now true of the women, too.

Liberty Vittert is a professor of data science at Washington University in St. Louis and the resident on-air statistician for NewsNation, a sister company of The Hill.