The shock factor

I hate the thought of mum being on her own. I want to look after her, make sure she is occupied and feel incredibly guilty each time I leave her in the house alone.
We needed to get back in to the routine of work so most of the week she is on her own. During the weekend we would try to arrange food shopping and always have dinner on Sunday together.
Looking after the dogs was a real pleasure for her so would ask if she would mind having them for the day sometimes.
Stress seems to make her worse. I have to say at this time there has been no diagnosis, nothing to warrant going to the doctors and as usual no appetite for broaching a tricky subject, this time the possibility of dementia.
Christmas was looming, always going to be difficult for anyone who has lost a loved one but the repeated conversations about how, she and dad were always working shifts and because of that she doesn't really enjoy christmas anymore, it's gradually been whittled away over the years, have become a little tiring. However …. she then delights in telling us that she loved to work over christmas, it was fun with the old folks helping them have a good time. I wonder how are we supposed to take that. I respond, asking her to think about what she is saying, does she realise she is telling me that she preferred being with other people than her family. Anyway, a subdued holiday and never to be repeated, going to make sure of that.
We are having conversations about neighbours and worry about what they are doing, are their houses safe, are they going away. Bin day, mum won't go out until they have emptied it and she has the bin back in place. Garden rubbish, green bags can be filled and collected every 2 weeks, endless debates over what can and can't go in them.
All of these little things are leading me to believe that the shock of losing dad has escalated the illness that I think she has.