Khloé Kardashian, Tristan Thompson, and the psychology of cheating

Congratulations poured in on Twitter Thursday for Khloé Kardashian after TMZ broke the news that the 33-year-old gave birth to a baby girl at a hospital near Cleveland.

But interspersed with celebratory messages for Kardashian were takedowns of her boyfriend (and the baby’s father), basketball star Tristan Thompson. The vitriol was in reference to reports that Thompson has been cheating on Kardashian — not just once, but regularly.

The wave of accusations, which reportedly elicited boos from fans at the Cleveland Cavaliers game, originated with a piece in the U.K.’s Daily Mail. Published Tuesday night, the report describes Thompson getting “up close and personal” with an “unidentified” woman at a nightclub in New York, replete with pictures and Snapchats to prove it.

Following that, celebrity news site the Shade Room released what appeared to be video of Thompson arriving at his team hotel that night in New York with another woman. But that wasn’t the end of it. On Wednesday, TMZ released footage that it claims is from last October showing Thompson openly kissing and canoodling with other girls.

Although it was shocking to many that Kardashian (reportedly) allowed Thompson to be there for the delivery, it has also stumped fans why he would cheat on her in the first place.

So why did he cheat?

Susan Winter, a relationship expert who has been featured by everyone from the New York Times to Cosmopolitan, tells Yahoo Lifestyle that a lot of it might come down to habit. “In Tristan’s case, this isn’t a ‘one off,’” Winter says. “He did the same behavior with his last (pregnant) girlfriend when he began dating Khloé. So, fidelity doesn’t seem to be in Tristan’s skill set.”

The former girlfriend Winter is referring to is Jordan Craig, a model and social media personality with whom Thompson has a son named Prince Oliver. Craig and Thompson’s son was born in December 2016, just three months after he and Kardashian were first seen leaving a nightclub together in Los Angeles.

According to Winter, this pattern of infidelity (which has earned Kardashian’s boyfriend the nickname Tristan “Third Trimester” Thompson) should be a red flag. “Past behavior is a strong indicator of future behavior,” Winter tells Yahoo Lifestyle. “If a partner doesn’t care to observe monogamy in general, you’re entering risky terrain in the specific. Although people do change and partners can mature, this behavior sets a rocky foundation for any partnership.”

Winter suggests that perhaps Kardashian and Thompson, although both public figures, hadn’t drawn clear enough lines about what their relationship was going to look like. “Dating a public figure tends to lower one’s odds of exclusivity due to the constant onslaught of eager suitors,” Winter says. “Both partners would need to be ‘all in’ for this type of high-profile relationship to work.”

Not everyone considers cheating to be this black and white.

In her Ted Talk on infidelity, famed therapist and host of the podcast “Where Should We Begin?” Esther Perel says it’s more complicated. “Affairs are way less about sex and a lot more about desire: desire for attention, desire to feel special, desire to feel important,” she says. “And the very structure of an affair, the fact that you can never have your lover, keeps you wanting. That in itself is a desire machine, because the incompleteness, the ambiguity, keeps you wanting that which you can’t have.”

Unlike Winter, Perel doesn’t consider infidelity to be the end of a relationship. “I look at affairs from a dual perspective: hurt and betrayal on one side, growth and self-discovery on the other — what it did to you and what it meant for me,” she says. “And so when a couple comes to me in the aftermath of an affair that has been revealed, I will often tell them this: Today in the West, most of us are going to have two or three relationships or marriages, and some of us are going to do it with the same person. Your first marriage is over. Would you like to create a second one together?”

Whether or not Kardashian and Thompson try to repair the holes in their relationship remains to be seen, but the fact that they have a child together suggests they might. Even if they don’t, says Winter, that’s a built-in happy ending. “Khloé‘s wanted a baby for a number of years,” she tells Yahoo Lifestyle. “It didn’t happen with Lamar. This baby may be the real (and lasting) gift of their relationship.”

Read more from Yahoo Lifestyle:

• Kim Kardashian’s makeup artist wants Meghan Markle to hire him for the royal wedding

• How to get the Kardashians’ Calvin Klein looks for less than $100

• Khloé Kardashian slammed for ‘Thin AF’ post and making light of mental illness

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