Sometimes you can stay in touch with an ex either as friends, or acquaintances, or just for the purpose of knowing what someone you were once close to is up to. Other times, you just need to cut off all contact, because they've gotten into your head so deep that everything they do seems manipulative and angers you. As long as there aren't kids, money or real estate involved, it seems like you need to just let this girl fade oiut of your life by making a conscious decision not to deal with her. Maybe down the line you can be more in touch, but judging by the fact that you need to vent here, you're still too caught up with whatever feelings you have for her to deal with the situation rationally. Good luck!
