Might be a bit depressed, might be a bit bored, might be content that she’s not in any great hurry to get anything done from one day to the next.
[edit] There would be other symptoms of being depressed – not seeking company would be one of them – if she’s socially active she might not be depressed as such. But while theres lots of social activities available to older folks they’ve not necessarily got the depth and interest of a good friendship of relationship, so people can become bored, even if they are busy, rather than depressed [/edit]
Sometimes becoming single / widowed sends people’s time-keeping all awry, couples take queues from each other as to when to eat and go to bed etc and that can fall apart when one goes. Me and the gf each occasionally have to work away from home for extended periods and when one of us is away the other keeps forgetting to go to bed and we end up pootling around at 2 or 3am.
The question as to whether its a problem depends on what quality of sleep she’s getting. If she’s going to bed early and getting up late but sleeping badly in between then thats maybe a sign of not having enough of interest to do through the day and that she’s going to bed early because she’s bored rather than because she’s tired. If its all good sleep then I’d think that would be fine.
It is as if she is hibernating.
Do you mean these longer sleeps are just in the winter? Some people just sleep more in the winter (if they’ve not got a driving force like work to get them up).