I figure, for my particular situation, it's okay.
She's on my facebook (which states I'm male), and knows me by my transitional name (Richie).
But that's not going to excuse me from telling her.
I'd just rather do it in person.
But everyone's different.
I don't know if they have this at your college, but at my school, we have "amnesty week", where, if you are unhappy with your housing situation or don't get along with your room mates, arrangements can be made for the room mates to not live together anymore.