The word family is supposed to mean encouragement, love, trust, loyalty, decency, and honesty. If you don't feel that's what you are receiving and there is no point to move forward without mass amounts of anxiety, stress and issues then that's your decision to cut them off or not. You can have some decent memories with bad people. I had some decent memories with my family but they are horrible people and I was better off without them. I personally have no regrets. It hurt me to have to do it but not because I missed or loved them anymore. I felt that for them at one point and they took that away by their own choices. You can find family in a partner, a friend, a pet, etc. If your dad shows up, you can just not answer the door or call the police if needed. It really is up to you. You don't have to talk to any of them or be around any of them. You are allowed to make your own decisions. But choose wisely, once some bridges are burned there is no rebuilding them.