I may be the #145 person to pen down his thoughts on your issue, but here goes...
I went through the same thing as you when I was in my campus years. It was like I can't let her go and she is the only angel in the world bla bla.. but you know what? Just after graduation and clinching myself a job, I manage to get even better girls and bonk really good ones at a constant rate. Lol.
When I come to think about the girl back in the campus years, I really laughed hard. If I could go back in time, I would really like to kick myself hard and tell myself that "Just move on you piece of arse! Lots and lots of girls are waiting for you!"
So my advise...Just move on. I don't know if it's the sex or feeling that hooked you really bad to this girl, but I can sense that you are emotionally too attached to her..so yeah, no worries, once you find a new girl and hook up sexually or emotionally, you'll be on the track