Listen, it isn't like he is going around looking for married and non-single women and trying to have sex with them. Most of the time they are probably just really upset with their relationship or just permiscuous girls perhaps and are out on the town.

I am not even considering the fact that the women he is talking about have relationships. That is a problem they have and need to deal with. And I do not think you should knowingly go out with someone in a relationship unless you both love eachother in which case the girl should break up with the old mate.