I believe you. There are certain behaviors and scenarios that can trigger past trauma that can cause a ptsd episode. I can experience that myself. People that suffer from ptsd try to avoid things that can potentially set off one of these episodes.
Remember though that you are an adult now and when someone is being an azzhole it’s on them and not you. This is YOUR home and your father is just a guest. When your husband is there sit your father down and let him know that he is not allowed to disturb your home.
When someone chooses to bully then they need to know it’s not allowed.