A lot of people here are telling you to "just forget about it", which honestly does jack and shit for you. OBVIOUSLY you want to forget about it and move on, but sometimes it is almost impossible to do.
I still think about and dream about the girl that broke my heart almost 10 years ago. I won't go into specifics, but the point is - some of us still feel what you do.
I think that the best remedy as far as "getting over it" goes, is one of the hardest things that there is to obtain - Closure.
You are still beating yourself up over a "mistake" you made so long ago, and no matter what you do you can't live it down. The relationship likely ended on a note that you didn't want it to, and now you are suffering from the agony of feeling about things that "could have been".
We all know that this other person has moved on, matured, grown, and is likely a totally different person that he was 7 years ago. But those of us who still feel these things only think about how wonderful those people were many many years ago, and we imagine "The Wonder Years Version" of our beloved.
The remedy? Get closure. Send a letter to the person that you think about. Spill your heart and tell them all those things that you have always wanted to say. Apologize if need be...whatever you want to say to get it off of your chest. At the end of it, let them know that if they never want to talk to you, you would understand, but that you needed to do this.
If they come back and want to talk to you, then perhaps you will finally find out what happened to them and see where they are now in their life. Sure, the idea of re-initiating a relationship is not too likely, but at the very least you will have finally said all those things you wished you could have so long ago.
One of the best - and most tragic things that ever happened to me was when a girlfriend that cheated on me (multiple times while I was overseas in the military) finally called me 4-5 years later and cried and apologized. It was one of the most relieving things ever, because finally I got the closure I had always wanted. We only talked for about 5 minutes, but it was a huge weight off my chest.
(It was also tragic, because the biitch wife I had at the time demanded that I never speak to her again. Me being pussy whipped at the time, buckled and "lost" her number after that conversation.)
I have never spoke to her again, but I would give just about anything to talk to her again just to see how she is and where she has gone in life. I don't dream of this particular girl like I do the other one, (I never even said I loved this girl) but at the very least I finally was able to say what I had always wanted to.
"It's Ok. I forgive you."
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