He will be less devastated if he knows that you are okay, and you will stay okay and be there for him. Enjoy DD today. Go for a walk in the crunchy leaves, drink hot chocolate, listen to your favorite music together and dance.
AH is showing you who he is.
I am so sorry it's what it is. Treasure all the good things and people in your life. Put your life force in all that you love.
Don't let AH take that force from you. How can you best care for you, given what you know to be true?