Oh love, I am so sorry you've received this message. How horrific!
I think not responding is a wise decision. Perhaps reporting her to facebook as that is abuse and is not acceptable.
Are you going to be safe? Could you do something to soothe yourself while you're feeling like this?
Keep talking here if it helps.
Please, please don't take on her words. You are none of those things. You are a wonderful, kind, strong person that has had something horrific happen to them that they don't deserve.
Sending so much love <3