So I think my father in law is going psychotic.

My wife was informed by a relative that her dad has several facebook accounts where he pretends to have conversations with my wife, he made an account with her image that he logs in and out of to carry on the conversations with. She went no contact with him after he threatened to kill her and we kicked him out, after offering a room to him because the house he was staying in was not habitable. Most of the conversations are "woe is me, I did nothing wrong"

Is there anything we can do? This is just crazy

ignore him. people like this usually don’t recover, they spiral further