Both my parents have dementia, in my mother's case very advanced Alzheimer's, which we noticed the onset of nearly twenty years ago. My wife and myself now live with them virtually full time in their own home.
My mother cannot put two words together coherently; my father is somewhat better but still has significant dysphasia and dysgraphia. Virtually everything you would consider part of a normal daily routine is either difficult or impossible for them. They are effectively pre-school children in their level of dependency, but much heavier to pick up when they fall (it's not a five-minute or one-man job), and their learning curve is one of exponential decay.
My mother is doubly incontinent, and if uninvigilated uses random places in the house as her toilet, sometimes several different places for one toilet trip (nappies go on, but don't always stay on long enough to be any use when they're needed). She also has wanderlust and recently went missing for a few hours at nightfall, entailing frantic scouring of the neighbourhood (she was waiting at a bus stop about a mile from home) and police involvement. Wearable trackers are out of the question, because, like virtually all precious or apparently precious things that come within her gaze, they would be consigned to a safe place, i.e. effectively lost or binned, in very short order. Only last week my father couldn't find his wedding band (a very heavy 22ct 1904-vintage one that had belonged to a grandfather); after three hours of searching he found it wrapped in toilet paper – in the toilet bowl; miraculously, he had thought twice before flushing.
But we find ways to keep our spirits up, with things like our own take on neuro-linguistic programming: "onwards and downwards" can be a surprisingly heartening motto if you say it often enough.