Last night I found out a good friend of mine was sleeping with another friend's wife. My good friend is single and he is not friends with my other friend, but they do know each other. My loyalty is to my good friend, but I think what he is doing is wrong. I told him that and said I thought he should stop. He said okay. Even if he does stop he already slept with her. I know if I was married I would want to know if my wife was banging some other dude. I'm so torn!