I need advice on whether or not to end a relationship...

I've been dating a guy who has always been great, for two years or so, but I don't know how I feel about him anymore.
I have issues with depression among other things I'm sure, but it has made me so dependent on interaction with other people recently that I can't spend an extended period of time alone without breaking down. I'm not the most socially active person, I have friends, but there is almost no one I trust enough to really open up to about the way I feel, basically my boyfriend and one close friend, but she's hours away.
I understand this is hard on him too, me being so needy, but if he really wants to be together shouldn't he be there for me?
If I give him the time to himself that he claims he needs, we don't speak unless I initiate conversation, which really only happens when I'm seriously desperate for anyone to help make me feel sane, but I'm usually on my own now. He only seems to care or at least show it in some way when we're physically together and he can see that I'm upset. I know it stresses him out, but I'm fucking stressed too, he's the only one within hundreds of miles that I am comfortable talking to about my feelings and now I don't know if I'm crazy or if he's an ass.
What do you think?