The thing is, having a mental illness or a neurological disorder does not excuse someone from inflicting fears and violence onto others. The best thing you can do is contact the police, again and again. That IS your boundary. You will no longer live in fear in your own home. The police will help de-escalate her behaviours and create a file. If she's non-compliant, they will take her for a couple hours, depending.
You've tried to help her and this is her problem. Dig your heels because she needs someone in her life to do just that.
I know nothing about APD.. so maybe my advice isn't helpful. I'm sorry you're going through this.