For many months mom never spoke of dad. He passed away in June of 1982. She still acts like she doesn't know who he is. My children and grandchildren have visited her and she doesn't know them at all. Even though my daughter was quite close to her for many years, mom acts like she doesn't know her.
Mom is still alive bodily.
Love your parents as they are. Love them even though they don't seem to know you. Lean on other family members for help and guidance. This disease is a horrible way to live. Take each day as you can.