had an episode at Christmas where she suddenly could not walk so was hospitalised again for 6 weeks. My father had this, from taking himself independently by nus to shops and appointments, to not being able to weight bear, in less than a week. In his case, exacerbated by not taking his diuretic tablets. He was living alone without carers, but on his release from hospital he started having carers twice a day, meals on wheels, and frequent visits from the district nurse.
We didn't get as far as full time care, and after another couple of hospital admissions and another fall, he was admitted to a nursing home as an emergency, and has stayed there since. We discovered that his weight had dropped by two stone.
The nursing home were able to make sure he took his drugs regularly, and that he was eating well, so he's regained all his weight and lost his oedema.
You may need a nursing home not a care home, and one that takes dementia patients even though your mother doesn't yet have a dementia diagnosis (neither does my father). Apart from other things, homes which accept dementia patients have locks on the doors which means residents can't leave freely.
Requiring evidence of being able to pay for several years is quite a common thing, although our home has never asked for it, possibly because it also takes council-funded residents, so if he ran out of funds, the council would take over. Owning her house should cover it, but they'd want proof that she did in fact own it.
The change will be difficult, but it will come some time, and possibly earlier rather than later is better, while she still has understanding of what is happening.
If you search for care homes on the Care Quality Commission website, there is a box on the RHS of each care home labelled Specialisms/services - look for homes that include "dementia".
www.cqc.org.uk/what-we-do/services-we-regulate/find-care-home
Look for quality of care rather than quality of facilities. The most expensive homes are not necessarily the best. If there's a likelihood that her money will run out before her body does, there's some point in choosing a home that she will be able to stay in if the Council is paying, though it's hard to see the future, If she doesn't already get it, look into getting Attendance Allowance, which is not means tested. People who are Council funded in a care home can't get it, but if she's self funded, she can.