My last 2 cents on this issue........... Like many have suggested....be careful of the ultimatum. It rarely, ir ever, works. The fact is that you've talked about this with her several times already. Has anything changed...has she made any effort to understand your feelings on this subject? I would guess she hasn't.....and you know why.....because she knows she doesn't have to. I wouldn't issue an ultimatum and deal with all the drama that would follow. She will run out the "you don't trust me shit" in attempt to make this issue all about YOU. If you go the ultimatum route it will guarantee a big fight.....no satisfactory resolution....and more of the same shit. The answer is to just ditch her....no drama.....no fight.....no tears....no anything. Do your best Clint Eastwood impression....and walk away. She has to come to the realization that you aren't willing to put up with her high school bullshit. This is not the kind of thing you can do halfway....it's all or nothing. Anything short of walking away...not answering cell phone calls...and generally ignoring her will not work. Either she figures out that you aren't a pussy and that you can't be pushed around anymore.....or she doesn't. Either way...you win. Believe me...as sure at the sun is going to come up from the East tomorrow....I'm right about this. Exit this kind of relationship with your self respect intact.