My parents are in denial

My parents are in denial that we are moving out of state. I have told them over and over again that we are moving and to this day they are still denying it, my husband has been living in a different state since March we are planning on moving down there with him in July. We both have better jobs out there and I’m just now going to be able to take my son to give him a better life from his abusive biological father. How do I get it across to my family that we are moving whether they like it or not it’s getting really close to our move date and I feel like it’s going to hit really hard when we move if they don’t accept it prior. My mother has told me if we move to never call her again and will even talk crap about my husbands father to try to get us to stay. If we do stay I will lose my job opportunity and my son will go back to 50/50 custody with his dad, while my husband stays in a different state to provide for us.