Exactly. Your father's behavior could stem from something as basic as he himself being the product of a dysfunctional family and poor parenting. Not to provide him excuses but it could also stem from being unable to cope with stress. Behaving as such is not merely an indicatior of mental illness. I like the suggestion of trying to talk to him if the opportunity arises.

Still, his actions are wrong.

I took the time to research helpful resources for you. What became of that help and the other suggestions provided?