Hi;
It sounds like there’s something more going on here alright; but I wonder if she would get checked for sleep apnea.
You mentioned sleep issues, and I know that can cause a number of other problems like brain fog, depression, moodiness, and nastier things like stroke and heart problems.
Apnea may not explain all her issues, but it was my first thought.
At this point, it might be worth simply having a loving, straightforward conversation with her and see how that goes. Offer to go with her to drs appts. If she’s not receptive, at some point you may need to enlist the help of outside parties, like her dr or social workers, making no attempt to hide it from her.
Best of luck to you; I know how stubborn aging parents can be, and she’s really not that old.