Okay, I'm going to be a little blunt and probably should folllow my own advice here ...
But he's TELLING you he's involved with someone else and you're still talking to him? He's asking you about his GIRLFRIENDS husband and you are even indulging him in giving him an answer?
I think you need to stand up for yourself and WHEN. He starts talking about anything that has to do with Ow or anything you know is a lie. Stop him right there and end the conversation.
You are not his friend. You are his W... don't let him treat you like a buddy
