It's for this reason I don't think living together when you are young is a good idea. I don't really see how this can be fixed, other than trying to avoid each other as much as possible, sleeping away, etc. It's never a good idea to rely so heavily on someone else for your living arrangements. Maybe your parents can help you rent a room in someone's house, or something?
Oh, and for the record, it's "separate", not "seperate".
Relax... I'll need some information first. Just the basic facts - can you show me where it hurts?