I want to contact him but he hasn't contacted me. Breakup advice?

[Tamika]

I'm a 21 year old college student and was dating this guy for about 6 months. I felt he was perfect for me. Well mannered, polite, handsome etc. We never really got to the relationship stage but was close and faithful to one another. One day I overreacted about something's he put on twitter and stopped talking. Then a week later made up and decided to move forward. About 3 weeks later he decided he really couldn't get over it and is no longer interested in trying to build a relationship with me. He said he just wanted no strings attached type thing. It's been 11 days since we talked and he hasn't tried to call or text me. I can't help but think about him ALL the time. I really thought he was going to tell me happy birthday two days ago and he did not. Nor did he tell me Merry Christmas. So it's very disappointing. I thought maybe if I didn't contact him he would miss me and call me but that's not the case. Do you think he even thinks about me? Should I contact him? Or should I continue wondering and hurting and trying to get over him? For some reason it takes me a VERY long time to get over a guy (like 1 year+) so any advice is appreciated.