It's true. Since I have been single again I have faced this situation many times, men hitting on me and then finding out they are in a relationship already but, "unhappy," etc. I never had any desire to get involved and often found much joy in giving them a lecture. Once they realized they had no chance, they would switch the conversation to a therapy session and the truth would come out. Mostly they just seemed extremely selfish, thinking they did nothing wrong in their R and it was the other person's fault. Why they didn't end the relationship always had a lame excuse -oh, I'm going to or something like that. The point is I could have been OW. But even when I was at my lowest low, isolated, lonely, hurt and desperate, I still didn't go there. What it takes is being selfish.