How do I deal with a mean and nasty father?

Do what seems right to you my Mom is 91 and it is too late to change plus she plays the deaf card whenever she is confronted. You can either take him to task about his behaivor or remove yourself from the area or not respond you have to do what gives you comfort and makes your life less stressful you may have to try many things before you find a way to deal with it also his age and health issues is this an old problem or something new are you his main caregiver is there a support group you could attend how is his behaivor affecting you are their others who can share your burden-I know you will get lots of support here,