Most Helpful Guy
Hi man, though I can't relate to that exact situation, I CAN relate to not being able to let go of a girl who, by all rights, should be in my past.
I have been absolutely, 100% infatuated with this girl, who I never dated (she rejected me, long story). I thought we worked great together, we had a chemistry that was crazy, I really thought we would go somewhere. I got brave after about 2 months and asked her out, she said no, we dragged the friendship out for another week or two and then got into a huge argument because she was ignoring/avoiding me and I haven't talked to her since October 24th of last year.
Not one day has gone by that I don't think about her, that I don't question my decisions, that I don't wonder what might have happened if I had done just one thing differently. I suffered a brief period where I thought I hated her, where the thought of her would piss me off, but it quickly faded into a longing to at least recover the friendship we once had.
Now, almost a year later, I'm still just as full of what I consider love for this girl, even though we never dated and despite the fact that she gave me the worst hurt I've ever received from another person. I've seen her with 3 other guys, shitty each and every one of them, and wondered why I can't move on when she so clearly has. The one girl I've talked to in the long period between last October and now, I pushed away, comparing everything to my experience with the girl I could never have.
I've turned to a number of different ways of trying to take control of my feelings - I've written raps, once I wrote a 5 page letter to her, I've confided in close friends, I even talked to a counselor I've been close to since middle school, and I still have these feelings. Everyone tells me to move on, and trust me I have tried just like you, but it's a hell of a lot harder than people think.
If you take anything away from this long reply, let it be this: first and foremost, you are not alone. But you should try to focus your feelings on something else, be it a song or poem or anything you can use to express your feelings. Confide in someone close to you - even another woman (you'll find they're very understanding in this situation). Just sharing with another person can work wonders.
I don't think I'll ever truly get over the girl I lost. But I - and you - should learn from these experiences we've had and use them to find better partners, as difficult as it seems.
I hope this helped you man. Be strong!