Really do not understand the male population

U know i've tried to figure them out and they dont make any sense to me. All my guy friends keep saying guys are so much easier to understand than the female population I do not believe that. For example I have fallen for a guy who to me is wonderful except right now cuz god only knows what has crawled up his ass. We've known each other for 11 yrs and have been on and off for 3 1/2 yrs. I go to bed thinking about him. Things were going really good we spend about 3 weekends in a row together mainly cuz 2 of those i was the DD cuz his best friend was leaving for military. Then I made dinner and took him food on Wed 2 days before his bday gave him a movie, and a 6 pack of MGD plus the card. Then i sent him a text friday early early early morning to tell him happy bday and he said thnx since then I have not heard from him. I had sent a text on Sat. to see if he wanted to hang out sometime this week no reply. Wed. was better than i thought it would be. Normally he sits on one side of the room and i sit on the other side but this time we sat next to each other the whole night and then when it was nite time he actually carried me into the bedroom which was a first. I woke up the next morning with him still holding on to me and thats not like him so why the hell is he being a dick now? Everytime I think i'm getting closer to him he pushes me away like this and i dont know what to do. I dont really want a relationship right now i like what we have going on it is what it is i cant explain it. But i love the fun we have. I can actually be me and not have to worry about talking to someone and him getting mad. We made a promise that if either of us wanted to see someone we would tell the other person and we've been real good about keeping that i just want to know if hes acting this way cuz there is someone he wants i dont know im so tired of trying to figure him out.