My mother could never accept that there was anything wrong with her. Sometimes on her good days, in the odd moment of lucidity, she seemed to accept that, as we explained it, the wires in her brain sometimes got crossed and it made her do/say daft things. But as it progressed this happened less and less. By the end, I had ceased to be her daughter and had become an old school friend whom she didn't like very much. My OH, who had always been one of her favourite people, was now someone who had come into the house and taken over and (she was convinced) was there to kill her. Her physical disability meant she couldn't get around much under her own steam and firmly maintained that she was being kept prisoner - not in her own home, because she didn't recognise it as such. She wanted to go home to the house she grew up in and became very upset when we tried to explain that it hadn't been in the family for many years.
It was as though the last fifty years of her life - her husband, own home, kids, work, widowhood - had never happened. That everyone insisted they had when she seemed to have no knowledge of them appeared to upset her very much indeed. I don't believe she was happy at all. She only seemed to improve in spirits a little after she moved to a care home. It was somewhere completely 'new' and she seemed to accept that and the fact that she was 'getting older' (she was 81) and the staff there 'wanted' to look after her. Sadly she had a heart attack after just one month there. Probably a blessing in some ways because we just don't know how long that lift in spirits would have lasted.