Is it over?

My SO and I have been in a happy relationship for about 5 1/2 years now but lately it's just like things have changed. We moved across the country together so we could attend the same college and live together but things just aren't what they used to be. We used to hardly ever fight but now it's like a constant battle between us and nothing ever gets resolved, our sex life has declined like crazy, and it's always me saying sorry and half of the time I don't even know what I'm saying sorry for. We hardly communicate, but we also come from very different backgrounds so he knows how but I've never really been able to, it sounds stupid but I really just don't know how to talk to people when in a confrontation so I can see how he gets frustrated. Like I said, nothing is ever solved between us. I feel unhappy most of the time and honestly I feel like I'm being put last. He's a college athlete so when I tell him this stuff it just gets turned back to me not being supportive and that I've "never been like this" until now, idk. He has no drive toward his future career or school, just his sport. I know if you're unhappy you should leave but I am happy with him sometimes, and I left everything I knew (friends, family, etc) back home so that I could be with him and to be close to him. I've even tried thinking of ways to make him break up with me because I just don't have the heart to do it.. My heart breaks for feeling like this but I just don't know whether to call it quits or keep fighting. Please help. Sorry in advance for the lengthy post.