I do, so very much wish I could help, but the truth is, I can't. Neither can the NHS to be honest. It's a brutal disease, which I found out a few years ago. One day, I went in to see Mum at her dementia home, and she was in a katatonic state. They had given her a chemical cosh. They promised it...
So sorry to hear your story. My Mum had dementia for several years before she died two years ago.
It sounds like your Mum needs help. The thing I would say, is to act sooner rather than later, so that you have time to do research and make the right decisions, and are not forced to act in...