[BlackArcher101]

I would approach the police and ask what your options are here. If you call them, I believe the only thing they can do is go to the house and if both say they are fine, there is nothing they can do. This might escalate things after they leave. So ask them first what the best way to approach this is.

I agree with Bring_Back_Shantz sentiments though. Her safety is the primary concern here, not to keep her as a friend. In the end when things are better, she will hopefully realize the good things you've done to help and reverse her decision.

When the police get involved she is going to need a support network or else she will probably go back to Don. You say she's very limited in this regard with very few friends and very little furnishings, so this will be the hardest part to deal with. Try to increase that network before anything happens so that the chance of her going back is decreased. Speak to others that are concerned about her and have them ready to support her. Don't have them do it yet though as she might be offended you told them.