Hi @denisefrey, my husband has moderate Alzheimer's Disease, diagnosed in 2019. For a while, he was resistant to showering and washing his hair. He broke his hip in Jan. 2022 and while he was in rehab, I had the tub removed, a shower bed installed with grab bars and added a shower seat that hangs over one grab bar. When he came home, I realized it was easier to get in the shower with him, then give him instructions from outside. Now he loves to shower and washes his hair whenever we're in there - usually every other day. Then he thanks me for the wonderful shower. When I asked him why he didn't like to shower before, he said it was because he didn't know what to do.
Prior to all this, I noticed that he wasn't cleaning himself very well when, doing laundry, I saw his underwear. I installed a bidet toilet seat cover, and while he was resistant to it in the beginning, he's taken to it very well.
I remember my mother-in-law, always a fastidious woman, told me she hated showers in her later (declining) years. She said they felt like sandpaper scraping her skin.
Of course, everyone is different, and this may not be helpful at all for your situation. I wish you the best.