That’s a question better asked of a therapist who can hear your whole story. These situations are often very, very complicated — because people are very, very complicated. Your father both abused you and supported you. You continue to benefit from the life he gives you. It is often difficult for people in your situation to sort out their feelings and obligations in the present when there has been a difficult past.
You report that you have the emotional resources to deal with both the past abuse and your father’s dementia. That says to me that you also have the emotional resources to deal with the complexity of holding both gratitude and hurt. I think you would find it very helpful to talk to a therapist about how to do that in a way that has integrity.
I wish you well.