What a tough spot to be in, I'm sorry your having to go through this it must be really frustrating. Personally i would recommend seeking counseling for yourself, maybe specifically for assertiveness. I understand you sometimes feel guilty about standing up to him because he has bi-polar and you want to be accommodating...but what is that accommodating his inappropriate behavior really costing you?...whats that costing him?...anyways just my personal opinion...good luck and please keep us posted.