Abusive father

Its really unfortunate.... but also really appreciable that in spite of such tough conditions you managed to come out of it and build up a good life out of zero.....however, bluently speaking you do not have any option against them after such a long period. On the contrary they being old now have certain options against you such that your father can claim maintainance from you if he is unable to maintain himself from his own income. Though he might have torchered you but still his legal rights against you are not hampered by that. It is better if you forget the past and move on with your life and do not keep any relations with them if you feel so.