This is how you stop having anxiety attacks and hoping she'll come back:
1. You realize that she's not worth feeling like shit over. Because she's not if she isn't falling all over you and wanting you and only you.
2. You consciously change the subject of HER when she pops into your mind. You MUST stop wallowing in your memories and You MuSt stop your 'what if' type OSD thinking on her. If you need help with changing the subject of her from your mind then put an elastic band around your wrist and snap it everytime you find yourself daydreaming about her.
3. You keep busy doing things you have to to (work/school) and especially with things you LIKE to do with people you like doing them with. If you've always wanted to start a hobby doing something that interests you, now is the best time to do that.
4. You block and delete her from all social networking sites so you can't creep her. Creeping her just keeps her rooted in your mind and your thoughts of what ifs.
5. You tell your friends that You do not want to hear what she's up to, whats she's doing or what she's saying. Period.
6. Finally, but most importantly, YOU accept that it's over and that you're better off without her and her flakiness. Why would you want to be with someone who plays WoW 24/7, looks pasty and white from being inside 24/7 and has no motivation other then getting to the next level? bleck, pfffft, ewwww!
There's better out there, son. Get feeling better so you can find her.
7. (Voluntary) You come back here in a couple of weeks after implementing one through six and tell us how you're doing.
Good luck
“The willingness to accept responsibility for one’s own life is the source from which self-respect springs.” ~Joan Didion