17 & don't know what to do with a relationship

I'm staying with my boyfriend for the wrong reasons and I wanna stay with him but leave him because I feel like he doesn't care anymore. We've had many arguments about so many dumb things. I know, what to 17 year olds have to fight about? I'm just stuck right now because he knows and I know he is horrible at relationships ( I'm his second girlfriend ). We actually dated last summer and it was the worst because he knew absolutely nothing and we were only trying to hook up. But then we broke up because he said "he feel in love with another girl." And he contacted me a few months later, we talked for a long time and started dating again. I don't really want to make this long, I would just appreciate suggestions or advice on what to do. We believe we aren't right for each other. But we're both blinded horribly by each other. We wanna be together, and not at the same time. I'm sorry this is long.