Will I find love again? I keep dreaming of my ex.?

He and I were in a relationship for close to five years, since we were 15 until the age of 20. He was my first and only love, lost my virginity to him, was my first relationship. I had many firsts with him. We broke up a long time ago in October 2009 and it's been 630 days since we last saw each other. We never speak, can count the times on one hand we did since breaking up. That really hurt me. He started dating someone else immediately after and they've been together since and last I heard are engaged. I'm happy for him, but I'm upset that I'm not in a relationship. I've dated and had things here and there with a few different guys since. None of them were anything special and I haven't felt sparks with anyone since him. It's approaching two years and I'm starting to feel like I'm never going to find love again. I'm going to be 22 in September and I'm starting to lose hope that I will fall in love again. I know I'm still young and that it's ridiculous to think like that but I'm fed up with the guys that I have been dating the past year and a half. I didn't feel anything for any of them. I miss being in love. I want that kind of closeness and I guess that's why I dream of my ex, because it's the only experience I have of it. I just want to fall in love again. Why isn't it happening?