You know why? because he did exactly what you asked him not to do. You communicated about how those comments hurt you. And he did it anyways, In front of your friends. He was inconsiderate of your expressed feelings, and I don't know how someone like that could make a good future partner. If stability and commitment are all you need, that's one thing. But commitment means more than not leaving. Is he committed to being your true partner? Is he committed to taking your feelings in to account? Or is he just committed to being there?
