Separate lives in a relationship (rant)

My boyfriend and I are in college. His program is very important to him and I support him. But I get SO irritated when he takes a night off from studying to go hang with the bros that he sees every day and then tells me he can't see me the next day because he has too much homework he didn't finish the night before. I explained to him that I always try to manage my time so that my work doesn't cut into our time together or my social life, but that got us no where. Keep in mind that I graduate in 3 months and then I'm moving back to my home town, far away. I just want to spend the time I have left in this city with him before we only see each other once a week at most. He sent me a text "teaching" me that we have to have separate lives outside of our relationship. I just didn't think that meant I have to feel like his last priority.