Hi
@KittyG and welcome to the Forum, or community of friendly and helpful members who have experience of many aspects of dementia. You'll find a lot of understanding and support here which I hope will help you.
I was sole carer for my wife for several years before and after her Alzheimer's Disease was diagnosed. I know how hard and all consuming it can be. This site helped me tremendously with good ideas and support. It led to me engaging a carer/befriender for a few hours once a week, giving me time to myself. I also tried a day centre (she wasn't keen and stopped going) and a few, successful respite stays.
I am not sure whether these may suit your circumstances but they could be worth a look. Finally, as I could no longer meet her needs, I took the hardest decision and arranged admission to a care home. That was 5 years ago and, though difficult at the time, I know that it was the best thing that I have done for her. She is content and well-looked after around the clock.