Hey everyone...got a little relationship struggles I guess?

Here is my story. When I was 15...now 23 I dated a girl from the age of 15-18. We broke up my senior year of high school because I will be honest I was very immature and jealous because my girlfriend was very pretty (almost thought she was too good for me). Anyways for the 1st 2 years of our relationship things were awesome. I really think I fell in love with this girl. Anyways things went south like I mentioned. Since then I have dated around and currently have a girlfriend of 3 years. Now my ex girl friend has also been seeing this guy off and on for 3-4 years now. We have remained friends and have talked at least once a week since we broke up. I still really love my ex even though I have a girlfriend of 3 years. Recently (in the last 2-3 weeks) my ex broke up with her boyfriend. She started calling me all the time which I can say I really enjoyed. I finally decided to see her the other night and was great. I thought maybe we would start things up again. Come to find out she wants to get back with her ex boyfriend.

So now that you kinda know the story I can tell you I've not been the same person since we broke up. I used to go out with friends all the time, but now I tend to spend time in my room playing around on my computer. I am a networking student in college so most of my time on the computer is doing hw. Since the break up I've lost my emotional connection to anyone except for my ex. I've also had a very short fuse. When people say something to me I snap. I've also began buying new things all the time to try and make myself happy for even a week. It's been 5 years since we broke up but I can't get over her. Recently I've been sleeping a lot and staying up very late. I have also began playing World of Warcraft. I think the reason I like the game so much is because I get so involved in it I forget about her. Just wondering what you all think about my situation and maybe some advice on what I should do. I don't want to be this way, but some times I can't help it.