My brother keeps moving back in?

My brother is 26 years old and lives with his girlfriend. They both split the rent and bills etc. Well recently the past few months they keep having relationship problems which causes him to keep moving back in with my grandparents, which is where I stay now. Today, me and my gf both just helped him move out from her apartment for the second time. I love my brother to pieces but here is the issue. When my brother moved out last year I took his old room because it was bigger and had the larger bed. Everytime he moves back in, I'm forced to sleep on the couch which sucks because I'm 6'6. And he takes the bed I was sleeping on. Also when he moved out I started paying the bills he had such as the internet bill. I'm work a part time job and a college student and I'm 20 years old. My brother never finished college or anything. Well now he's moved back in using the Internet I pay for. He uses my computer and plays games. My mother tells me it's only temporarily but I'm seriously getting fed up of losing my room when he keeps deciding to break up. What should I do?