Confront them, tell them how you feel, ask them why they did what they did. Show them you are better off without them. Don't get me wrong, everyone makes mistakes but they need to realize right from wrong.. if they already haven't.
Kick them to the curb. There is no reason why someone would be so cruel & want to hurt anyone.( Unless a child's involved like molestation, I'd be kicking ass.) I've had my x-fiancé cheat on me w/someone who I thought was a friend. I don't think so. Better to find out now rather than later.
