16, I hate to be a real downer, but I agree with some on here that she is seeing somebody else. I'd bet a lot of money on it. I wouldnt confront her, as there is no point, but SHE'S GOTTA GO!
She can go stay with a friend. She should of thought of her living situation before she dropped this on you.

I must have missed it, but I have not seen the poor kid acknowledge that she is seeing another..
He'll know for sure soon enough...
Were just trying to make sure it isnt via walking in on Dr. Dreamboat plowing her on his sofa.

Because as bad as it is NOW, the image of Doc giving him the old' shooter Mcgavin double pistols gesture (butt naked and balls deep) would be MUCH, MUCH worse.
Would be the best thing that could happen to him. *smack*, his hand strikes her hard on the ###.
"Come on! You're always so damn lazy when you're on top. MOVE IT! Quit making him work so hard and move your ### a little bit, would you? You know, doc, when she's on the verge, she really likes it when you shove two fingers five-hole. The faster, dryer, and more painful, the more she enjoys it. She'll object a little at first. Just trust me and fight through the bull####.
Now, if you'll excuse me, there's a bowl of Fruit Loops in that kitchen that's not going to eat itself."
Why the hell should he care who she's doing or where she's doing it? He doesn't. End of story.