So I've been speaking with this guy for the past few days I really like him and he really likes me. His ex girlfriend is really weird and is trying to get back with thus putting a strain on our potential relationship. He said she has no power over him and that it won't interfere with what is going on between him and I. I'm really worried that it might change, she's done a lot to him in the past: black mail, threats, still spreads rumours and a lot of other nasty things. He's pretty upset about what's happened and I told him I don't believe anything she's said about him. How do I cope with all of this?