Toxic friend

Hi, I’m in a bit of a situation with one of my ex friends, basically we were friends for a year until her boyfriend broke up with her and then wanted to get with me claiming that’s why he broke up with her, I asked her if it was ok for me and him to get together and she said it was totally ok, once we got together she got with my ex boyfriend who I was with for a year, she knew how much he meant to me and she did it anyways. We then

Talked it out and worked everything out and decided we should not be friends but we also shouldn’t have any drama. Then every guy I went after she went after too, three guys in a year and she dated all of them right after me, then I met my current boyfriend around July and we’ve been together for 8 months, she’s so upset over that that she has been sleeping around with my guy friends and ex boyfriends just to piss me off. So I don’t really know how to just get her out of my life completely and not worry about it.