Relationship Advice

My boyfriend and I have been together since January and at first our relationship was great. We were always having fun and having sex quite a lot. I got my apartment in may and he's still living in his barracks and working for the army while I'm in college. Its only about an hour away so he comes over on the weekends. I work a lot to make ends meet and it just seems like we never have any time together and when we do were just not interested in each other. I want attention but I never feel like he wants anything from me at all. We finally tried to have sex, which hasn't been good since August, and it was a complete fail. We weren't even really into it... I can't tell if its just me over thinking or what. He's done a couple of shady things in the past that compromised my trust for a while but I'm mostly over that. Thanks for anyone that tries to help.