Most Helpful Guy
You can't hurt people emotionally through a relationship, if they don't value the relationship to begin with. He doesn't care about you, loyalty, relationships, etc. You can't do anything to a person like that, by doing anything in your relationship. He values something else, but you likely have no control over those aspects of his life.
Most Helpful Girl
He is probably dressing up somewhere talking about girls as "bitch." If you want to revenge... well.