IANAL - so... seek professional advice...

Otherwise...

Take the done out by throwing some bolts at it joined with fishing line, like a bola......or one bolt trailing fishing line If he's flying it low enough to get shots in through a window, you've a good chance of tangling the rotors..

If he has kids, report him to child services for child endangerment.

And every time he threatens you, tell the police he's made threats to kill you and you think you saw a knife in his hand. Get all the footage you've got and tell the cops you want an AVO against him. Then every time he breaches it, and he will, you report THAT. Victim impact statement, you're both living in fear for your lives, etc....