relationship dying.

Lately my boyfriend and I have not really been on good terms. I'm always upset and he seems to not understand when I say I want more time. We barely see eachother and we have not had sex in 2 weeks!! It's so difficult and he says he loves me more than anything, and I know I love him, it's just hard when I feel like I'm on the back burner. But he is willing to try anything to help us out. How do we try and get a spark back in our relationship? Any ideas.