Here's Why Experts Say Affairs Happen + How To Repair In The Aftermath

Infidelity is a heartbreaking and traumatic experience that severely damages the trust and intimacy of a relationship—but why does it happen?

There are a myriad of reasons one partner might decide to stray outside marriage, of course, but according to psychologists John Gottman, Ph.D., and Julie Gottman, Ph.D., leading relationship experts and founders of the Gottman Institute, there's one big reason to keep in mind (and try to prevent).

When mindbodygreen's founder and co-CEO, Jason Wachob, asked the Gottman's what typically causes affairs, Julie quickly replied, "Loneliness. It's absolute loneliness."

As she explains, loneliness often arises out of the the "four horsemen of divorce," or the four behaviors that are associated with divorce: criticism, contempt, defensiveness, and stonewalling.

"One partner or another will be very critical of the other, very contemptuous, making the other person feel defensive. There'll be a lot of four horsemen until [one person] finally just can't take it anymore," she says.

And once that happens, "They start avoiding having conflict discussions, but as they avoid those conversations, they grow more and more distant until they're barely talking to each other at all—then there's deep loneliness within the marriage," Julie tells mindbodygreen.

Once this level of loneliness has set in, people are much more susceptible to seeking connection outside of the marriage. Julie notes that the late relationship researcher, Carol Rustbalt, also found that people with the greatest tendency to have affairs were people who compared their partner negatively to somebody else.

For instance, someone might have a nice exchange with their local barista and think, "She gave me a great smile. My wife never smiles at me like that." As Julie explains, "That's a negative comparison, and folks who had affairs were full of those."

The first stage of this process is what the Gottman's call atonement. As Julie tells mindbodygreen, "Atonement is absolutely crucial to healing from an affair."

In the atonement stage, the hurt partner can ask the partner who's had the affair any questions they want to, and those questions must be honored and answered transparently. "They also have to listen to the feelings of the hurt partner with as much empathy as they can," Julie adds.

It's worth noting that this stage is not about discussing what went wrong in the marriage. "We're just dealing with the consequences of the affair," Julie explains. To that end, the Gottman's note that if couples don't actually talk about the affair and confront it, the relationship is likely to end.

Stage two is is the attuning stage, in which couples start building "marriage #2." In Julie's words, marriage #1 must be left behind. "Marriage #1 has burned to the ground with the affair. An affair destroys everything in a marriage. Not only that, but it typically creates post traumatic stress disorder in the person who's really been hurt," she explains.

So in this stage, the focus is on helping the hurt partner heal (especially if they're dealing with PTSD symptoms like nightmares, intrusive thoughts, hypervigilance, etc.), as well as rebuilding trust.

Finally, the third and final stage of repairing post-affair is the attachment stage. The bulk of the heavier work has taken place in stage two, while attaching to each other in stage three is about reinvigorating your sex life together and renewing your commitment to each other.

As you both navigate your second shot at marriage, consider this a fresh start and a chance to "date" each other again.