When people cheat on their spouses, they’re most likely to do it with a friend, a coworker, or even a neighbor, a growing amount of infidelity research shows. And wives may be even more likely to have an affair with someone in their inner circle than husbands are. Part of the reason is simple convenience—proximity and opportunity. But scientists suspect that it’s also because cheaters often want out of their current relationships and are afraid of being alone.

So they split the difference, and look across the street.

“Most people who have extramarital sex do so with someone they know well,” according to a 2017 study in the Journal of Family Psychology. “People most commonly report having extramarital sex with a close personal friend or neighbor, coworker, or long-term acquaintance.”

This study took into account several waves of the General Social Survey, a massive dataset that measures social change, including attitudes extramarital sex. About 21 percent of men and 13 percent of women reported cheating on their partners at some point. When people cheated, 82.9 percent did so with a close friend, neighbor, coworker, or long-term acquaintance.

The findings echo several past surveys conducted by Ashley Madison-esque websites marketed towards people trying to cheat, but this is 2017 research was the first scientific study to focus on what kind of extramarital partners people are drawn to. And while opportunity, proximity, and the emotional connection of already knowing each other helped facilitate the affairs, couples need to experience other issues in their relationships in order to be vulnerable to temptation.

“With respect to relationship factors, the association between lower relationship satisfaction and extramarital sex is a well-established finding,” study coauthor Mark Whisman, a psychology professor at the University of Colorado, said in a statement. Whisman and coauthor, Lindsay Labrecque suspect that, when unhappy people cheat, they’re looking for a way out of their relationship, but they do not necessarily want to be alone either. As a result, people don’t just cheat on their way out—they form new relationships, to keep someone else “on deck”. And it makes sense to do this with people they already know, no matter how messy that may be.

“I wonder whether married individuals who have extramarital sex with partners such as a close friend or co-worker are choosing such partners as a commitment to form a new relationship and, by proxy, to leave their marriage,” Labrecque said. “These partners possess or provide inherent qualities including emotional intimacy, closeness, friendship, support etc., and choosing to have extramarital sex with a partner with these qualities may reflect a preference for a committed and/or intimate extramarital relationship more so than a partner paid for sex or a casual date.”