I'm so sorry. I have very dear older people in my life and it will break my heart to lose them.
Your post brought double tears to my eyes because I am afraid I will see my husband "dead in the eyes" some time in the future, in denial of what he is dong to himself, still angrily blaming me. I hurt for him now, and I would hurt for him then. It's strange to be so alienated and so attached at the same time.
Blessings for you and your XA and your poor dear neighbor. May she rest in peace.