Originally Posted by
chrisinaustin 
Being that the dog is alone in a brand new environment with someone who's full of animosity and rage towards her, you should expect her to be cowering near the door.
Whatever situation has now developed between you and your roommate, and/or whatever poor judgement they may have exhibited, the dog is innocent.
Agreed. Dogs are very tuned into what people are feeling.
As someone else has suggested, make sure that dog is up to date on the rabies vaccine since your son has been bit, and address this issue with your roommate immediately.