I am so sorry, but I can totally identify. My husband was totally opposed to all things related to hygiene! He would fight us, almost in a state of panic. I thought it had to do with an innate sense of needing privacy. He would say, “It’s not right !” I learned to just bathe as much as he would allow, one body part at the time. Fortunately, he didn’t do any work or exhibit body odor. One of the first things I read early on was,”Nobody dies from not having a bath”.
As for toileting, I bought Seni disposable pull ups from Amazon which were much more absorbent than what I could purchase here at the drugstore. They also protected his skin and he never had a rash or sores. I would clip the seams first, making it easier to quickly yank them off. (The ones with Velcro tabs did not work for us.) Once they were off, he often would thank me 🤪 for helping him. I bought waterproof washable pads for the sofa and chairs to protect from leaks. If I got him changed once or twice a day, I counted it a success. I also talked to the doctor about medication that might help to calm him down. He was already taking Seroquel and Dr added a low dose of Ativan which was a game changer for us. He still would resist changing but would not get so very angry. I really think it allowed us to care for him at home his last days, rather than in a memory care facility.
Blessings to you. You are not on this journey alone.

I have no remedy but a lot of empathy!! I have found it comforting to know I'm not the only one experiencing this with our loved one. My husband's brother has an advanced stage of FTD and primary progressive aphasia. He's only 66 and we had to move him into a memory care community. We are his primary caregivers outside the staff at the community. He has refused to shower ever since being moved there. Then his incontinence became an issue, first with his stools. He had poop all over him, his furniture, and his room. Almost like he was playing with it. He still refused to shower. It takes two people to get him into the shower and he fights and yells the whole time.
I'm going to ask his doctor about the low dose of Ativan. I feel so bad for the staff taking care of him. He used to shower ever morning after his morning walk. He doesn't take long walks anymore (just stays in his room all day), so maybe that's why he doesn't know he needs to shower? My heart goes out to everyone experiencing this awful situation with their loved one.