My personality disordered ex who is in my estimation also psychopathic lived a torturous existence as a child. He was beaten until bones were broken, had urinated sheets hung to dry without being cleaned to show his friends how childish he was, had Christmas gifts kept on a shelf where he could see them until the following August with promises he could have them if he behaved but he never did well enough. In August they were donated to the Salvation Army. He was forced to eat what was on his plate and once vomited IN his food. He was forced to eat that as well. He was removed from the home at age 13 but by that point the damage was done. It was 1976.
I have empathy for my ex...which admittedly is difficult to maintain at times. It's more consistent to say I have empathy for the little boy he was. The grown man who could not or would not heal from such horrendous treatment CHOSE to abuse others. He CHOSE to rape his teenage niece. He CHOSE to call his own children bastards when he was angry and state they too should be beaten from the moment they were toddlers. He CHOSE to pull a gun on me twice. He CHOSE to lie, steal, manipulate, abuse and actively seek the ruination of anyone who loved him.
He, for the most part, was successful. But he chose every single decision he made to hurt another human being in any capacity. As such my empathy, for my own sanity, must also end at the point it became his CHOICE to do those things.
Obviously wholeheartedly my so not nearly impartial opinion.