You hit the nail right on the head. I have had to really work hard on my patience, which was never my strong suit.
I lost a close and old friend of mine to Huntington's disease last year, and I think that and Alzheimer's share a lot of commonality. I found myself spending a lot of my own mental effort focussing on consciously remembering how and who he was in the past. In particular the positive impact he had on my life, not long after I met him, which was immeasurable. I feel a bit ashamed I never really said it outright to him, but you often don't really need that with other male friends. I'm not sure that was the right approach, more just a blind, coping mechanism. That's tough but not surprising. I asked my friend if he felt if he were trapped or constrained or diminished in his own mind and he said he wasn't aware of it, although he'd researched it thoroughly when the symptoms first started. A kind of back-handed blessing maybe. Fuck I've made myself sad again. The memory issues are easier to deal with than the personality changes. I think she might be coming to terms with it even though she won't talk about it.