Whenever one sees a marriage fall apart due to adultery, one of the first things one hears is, “And I thought they were so happy!” Often, we tend to assume that couples torn asunder by an affair must be secretly in felt turmoil for years. More importantly, we assume that those of us who are happily married are then protected from the same crisis. In a provocative new article, a marriage therapist argues against these assumptions. She argues that a happy relationship is no guarantee against vow-breaking. I think she might be on to something.

In the October issue of The Atlantic, Esther Perel looks back on the scope of her counseling encounters with marriages in crisis over infidelity and notes how rarely she sees adulterous people who cheat out of a desire to flee a bad relationship. Often, she writes, it’s just the opposite. She encounters people who want to keep their marriage, the way that it is, and who don’t actually want to leave it for the other relationship.

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