A lot of men say they love you (mistress) not his wife. Or, that he is planning to leave/divorce his wife when this is a complete lie. Sometimes all a person is looking for is sex...different from what they are getting at home. I am not here to judge. Be careful. The fact that he is married to your cousin, could make it a lot messier throughout the entire family. Not a good deal for anyone.
Do you think messing around with a married man is bad? But he tells you he loves you and not his wife? But the wife is your cousin?
Thats bad because he might say that because your younger and maybe better looking then his wife and your cousin that's family you should do that because then when you look at them you are going to feel a strange feeling because he says he loves you but still with her.
Guy is lying to you. He's lying to his wife everyday he's with you. He's lying to you to ease your mind telling you that it's wrong to be with him.
Simply do one thing. Imagine if you were his wife ~ what would you expect from your cousin sister ? How can you trust a person who is not worth it...
Take it from me a man, all he wants is a piece of ass if he's married and once he gets it you're down the road left with a family feud to deal with and he's banging another chick. Don't get involved with married men or women. He'll get his eventually.