Help with Ex Girl Friend.?

I'm 19 years old and i dated this girl for 2 years. She was amazing, and she was everything to me. I did everything I could for her. And then one day she broke up with me. She said she needed space. for the next four months she texted me always asking how i was and sometimes saying she missed me. It stopped after awhile, and i haven't talked to her for a few months. Its been almost a year and a half since we broke up and for some reason I can't get over her. She is all I think about. I get dreams of her. I haven't even seen her in a year and yet her face is still imprinted in my mind. She was everything to me and she still is. I've dated other girls and it seems like none of them even compare to her. Every time I was with them all I could see was my ex. She was the only person I've ever known to make me feel like I was on top of the world. I Hide my feelings and depressions about this from my friends Because quiet frankly I'm sure there sick of it. I tell them I'm over her, But in no way I'm over her. My friends have taken me to Strip clubs and I just feel guilty for going. What do i do? This girl was the world to me, and I would give anything to get her back. I haven't tried seeing her or talking to her in months. What could i do to get back with her? Or Should i just keep trying to forget about her?