OOF, this is a hard jig for you, and things can go downhill really quickly. On the same note, they can stay "stable" for a while, but one thing is certain, you are never coming out of it. You need a diagnosis or noone will help - It's late, but the few things I would do. Get LPAO (sounds like you have done this) and see what you can do iro changing your own living set up, and selling your mum's house so she can live in an annex. (I am not sure about the deprivation of income stuff here, but it is definitely a thing) BUT if they get it bad, then the descent can be destroying. Even in their own annex. Even when we are cooking and cleaning, my mum (82) can no longer do almost anything for herself, including washing, toileting, dressing, has zero short term memory, no empathy, little recognition of family members, and repeats herself continually, (although at the moment she still recognises me, and a couple of others) .. She was fine at 79, My dad is still alive (83), and is absolutely adamant he will not see her going into any sort of care, and as such, he is bearing the brunt, other than the cooking and cleaning, I go round every day. He is luckily deaf (I never thought I would use those two words together) but mum will say the same thing over and over, it is not ten times, it is a hundred times. They really are a different person due to the disease. It's a horrible illness. They defo should not be driving, or if they are, not for much longer (sorry), it gets your short term memory and motor skills. Sorry I have gone on, and not been tremendous help, but I am with you in spirit xx