Allow me to be the devil’s advocate here and say we, both men and women, cheat because we make the decision to and because that decision is stemmed in selfishness. Of course, if you want excuses you will find them and we can justify anything. However, it’s me deciding my feelings and needs matter more and going after what will make me feel better without giving thought to how it will affect the person I am committed to. Like one of your friends said, it was a messed up way to tell his ex things had changed. That means, there’s always another way. But it requires us to be adults about it and that takes a lot of character. So we take the easy way out and justify our actions. In my opinion.