My mum is 87, diagnosed with AZ in 2015 and then with breast cancer just before Christmas. She is not having any treatment for the cancer other than taking oestrogen tablets - not that she takes them willingly! She still lives alone with support from us three siblings but had my sister not been made redundant last September and willing to take a career sabbatical to care for mum for 20 hours a week, ( we pay her £10 an hour plus petrol money which is a lot cheaper than an agency) we would have needed to employ agency carers.
Mum needs a daily visit to cook a meal and sort out domestic arrangements and medical needs but with a lot of technical aids, we are still happy for her to remain at home - but for how much longer, who knows! She is not incontinent and does not wander out of the house so is quite safe although she is pretty much in her own world, She has lovely neighbours who love her very much and will phone me if they have any concerns and the owner of the local shop that she visits most days also has my phone number.
We have a very sophisticated call blocker on her phone so no one can contact her unless I have added them to a trusted list, we have three security cameras and a door bell with cameras and microphones, the gas has been isolated to her cooker, we control the heating remotely through Hive and most of the important plug sockets have plates covering them - not much more we can do!
But we think we are still some way from needing to consider care homes, mum is healthy, safe and comfortable in her own home with little evidence of anxiety although I think she is rather lonely so we are thinking of employing carers to come in at weekends for extra visits.
I don't know when we will look at care homes, possibly once she is no longer safe on her own, maybe with falling, wandering outside or other health issues.
Everyone is different and some pwd need more care at an earlier stage than other people. If I was the only child caring for mum then I would not be able to cope.