The truth is, men get lazy and complacent. There could be other things that cause him angst like work or family problems.
I hear stories about girls leaving their partners because the men don't want sex ever quite a lot and he needs to know you're serious about this being a problem to you. I know of one woman who used to masturbate loudly right next to her bf in bed and he still wasn't interested!
You shouldn't have to compromise on the things in a relationship that are important to you. Confront him and let him know how unhappy you are, if he isn't willing to work on it with you then i'm sorry, he's not worth your time.