My mother was diagnosed with senile dementia which manifests different symptoms than Alzheimers,
She was already well into her 90’s and living in an independent unit of a staged care community. We had a caregiver come in for several hours every week-day morning and my sis, bro-in-law and I dropped over at least once a week to deal the following issues:
Trips to doctors and dentists
Refills of Rx’s
Fine-tuning wardrobe, necessary food (breakfast and snacks only) and paper and toiletry supplies.
Some checkers and double solitaire and general chivvying.
We kept post-its, notes and announcements everywhere.
Mother could dress herself, use the toilet appropriately, brush her teeth and wash face; she was able to take a shower as long as care giver was in the bathroom supervising safety issues.
Mother also remembered when to get on her walker and go to communal dining room for lunch and dinner. She never got lost and never behaved inappropriately at communal meals; was just very quiet (but she also had hearing problems.)
She never got angry or lost her temper or had tantrums, which often happens to Alzheimers’ patients.
She wanted desperately to stay in her apartment with her things and privacy (most of the time). So we honored that.
No simple answer to your question; if the wife is still comfortable with and has the energy to do the daily caregiving, then it is her call.