What happens when the person you believe abused you (but every now and then you still doubt yourself because of the fuzzy quality of the memories) is related to you and grows old? When he has been irresponsible with his money all his life and now can’t afford the care he needs? When he has never provided care to others but has always assumed that others will help him out when he needs it? When you feel for him as a human being who is sometimes confused and certainly vulnerable?
What do you owe to him when he is your father?