dealing with roommates and jerkin off...been there, done that.
1st roommate i had in the marine corps was some religious nut. not that there's anything wrong with being deeply religious, but this guy would try to preach to me. i'd be watching TV, see a hot chick, comment to myself, and he'd always have something to say about "saving yourself" or "that would be a sin" or whatever. oh, and he never left. getting quality time with myself was near to impossible.
second roommate was great. he'd hit the gym every night after dinner. i knew his schedule and i'd make sure i was there when he left. one day he said he wasn't going to the gym and wondered why i was asking. when i told him i was planning on squeezing one off while he was gone and that's what i did when he was at the gym everynight, he suddenly changed his mind and went to the gym.
had one roommate who would verify the time i was going to be back, and stated his intention to rub one off while i was gone. i'd always come back at least 1/2 hour later than i origonally said just so i wouldn't walk in on it.
oh, privacy was non-existant in our barracks too. we were in 2 man rooms and the bathroom was shared with the room next door. you could lock yoru bathroom door, but the lock was easy as hell to pick. had a next-door neighbor for a while that didn't care if he walked in on you or not. of course, he proceeded to show me his cock-n-balls when he was on test once and then explained to me that he was experiencing shrinkage and explained to me the ins and outs of test and how it affects your dick.
so really, you having to deal with one roommate isn't bad at all. try dealing with a barracks that's half full of perverts (and i won't deny it, i was one of the worse ones). guess nothing (besides tube girl) really shocks me anymore.