Join Date: Jun 2010
Location: Northern Virginia
I agree with VG, your manager was very unprofessional. Discussing the private opinions of other individuals is not something that should be taken to the workplace.
As for your roommate, I have learned over the years that there are some very eccentric people out there--some of them have serious mood problems, some are very narcissistic, and some just have no faith in the inherent goodness of people and just aren't comfortable with the notion of giving you the benefit of the doubt. Perhaps you did something at some point that upset her in a way that you didn't understand, which caused her to inappropriately lash out--this doesn't excuse her behavior but if you try understanding her rather than being angry with her it should be easier to move on.
At this point you're stuck with her, so you're unlikely to benefit from confronting her about it. Do your best to let it go. If you could convince your boss that you're a good reliable individual, you'll be able to convince your roommate too. Everyone has their personality flaws and everyone messes up.