How can I get back at my ex and friend?

me and my ex were together or 5 months.. and he used me for sex. and then starts going out with my best friend . I hate them both and I want to get back.. any ideas?

Don't have sex with people after 5 months.

Lose the so-called best friend, and act like you dont give a darn about both of them. Dont stoop to their level. Its going to hurt for awhile, but know you are better then that. Your friend is most likely going to end up in the same boat as you, when your ex is finished with her as well. You can either choose to be there for her, or throw it back in her face!

Yep. When their relationship fails, one or both of them will try to become friends with you again. And you'll just have to prepare yourself, and look down on them as if they're the most pathetic lifeforms in existence... and you'll be right!

thanx alott!