It sounds like your roommate may have the good old American attitude of "Screw you, me first". There is very little consideration for your fellow man/woman these days. It is not hard to give you some of the space you need, but there is no way I know of to enforce that without physical violence. If he wants to throw a fit, let him, as long as he's not being passive-aggressive. The situations I've been in with roommates really sucked. I just put up with it until I found a way out of it, then I immediately got the heck out of there. I would rather live in my truck than live with a roommate.