If I happen to have the pleasure of "knowing" another adulterer, myself a cheater, it makes me feel superior that I am desired more than the spouse. I big ego boost. You assume that someone in a relationship has sex at their disposal most of the time, so I am just dessert!
Yes, just dessert. If my wife does decide to fool around the other guy better realize this is just for fun. After just more than twenty five years, my wife is still crazy about me, as I her. We're never going to leave one another.