So I've been NC for 3 days, she obviously hates me, thinks I'm a stalker, is hanging out with some other dude (btw, she told me for months that she doesn't care about him, that he's awkward, that he's small, that he acts like a baby when he doesn't get his way, and that she would NEVER date him). So she won't talk to me because she isn't going to be involved with someone who doesn't respect her, shows up to her house uninvited, and harassed her through texts and emails. I've told her for 2 weeks that I'm going to leave her alone for 2 weeks, and I haven't been able to do it until now. I'm such an , I blame myself, but I feel so betrayed because all the of sudden, things have changed. My life is turned upside down without my best friend in it, and she has already seemed to be moving on.

I'm so lost

This is a toxic relationship and you're going through withdrawal of not being with her. It's addicting. You need to stick to NC. It'll be the really hard but it's the only way. As time goes on and you stay busy you'll get a better perspective of things. Right now you're way too emotional to think straight.

I'm sorry if this sounds rude, but you probably shouldn't have hooked up w/ her the second time. Even I could have seen this coming. Anything you guys used to do together, like any restaurants, bowling alleys, parks, places in the mall, etc, just stay away from. You guys broke up for a reason, so stop stressing. You'll find someone else, and they might not be the one for you, so keep trying. You'll eventually meet your special someone.