Her have been on here a few times. My mother in law has late stages of Alzheimers. She has been ok and going to the bathroom if we take her in the right direction but today she is very lethargic and not wanting to do anything or take anything. And she also used the bathroom on herself today. It has been a while since I've had to change Her. Is this typical?
The Alzheimer's will only get worse. You might want to talk to your family about what to do as that happens. If you feel in over your head now you might want to plan for the near future. You're going to need help.
Another option is selecting a good nursing home (NH) where she will get 24/7 care. The good thing about a NH is you won't have to lift and change your MIL. The bad thing is they aren't covered by Medicare. Your MIL will have to either pay out of pocket or apply for help from Medicaid.
I had an aunt who just died with Alzheimer's. She had a strong family, with three family members living on the property with her. They looked after her in shifts. Toward the end of her life, my aunt's children called in hospice. It made it easier for them and allowed my aunt to die at home -- something she wanted. Hospice was a godsend to them, because getting my aunt from the house would have been very difficult.