I recently posted a question here looking for ideas on things to do with my grandmother and got some great ideas. I noticed that my question was moved to another area I didn't see all about activies! How wonderful there is a whole area for that! *And sorry I didn't see that before, I should have looked more closely.* So now my question is, should I show my grandmother this site (or read some of it to her) and see if there she likes any of these ideas? I'm not even sure she knows she has dementia though? I don't want to upset her, but she has always been so independent and maybe having some say in the matter would help? Or is this one of those things were you pretend everything is normal?
If your grandmother was actively involved in her diagnosis and her care planning, then you should continue to be open with her about it. You don't have to bring it up, and certainly don't go on about it, but if she asks or if you need to explain something and it only makes sense if you're honest - then, be honest.
My mother took a lively, almost academic interest in her vascular dementia when we were talking to her older age psychiatrist and community mental health nurse, for example; but that's not to say that she applied the information to everyday life. It never made her realise, for example, that she needed to take extra time to think about things before getting up and tottering round the house in spite of the falls risk... well of course it didn't, she had dementia!
I like FF's filing analogy, that's a good one (and sometimes some fool must have gone and pinched and hidden the key!).
Certainly, if your grandmother does ask what's happening to her, it's useful to have ways of explaining that will make sense to her and reassure her that she's not going crazy in the way that people can be so fearful of. Talking about brain function rather than memory loss, for example, emphasises that this is a physical condition with physical causes; this approach can be more "acceptable" to people who come from a time when mental ill-health tended to be hidden away as something shameful.
Find out as much as you can about what kind of dementia affects your grandmother - does she have Parkinson's, by the way? You mentioned a severe tremor, I think? - so that you can have explanations ready for her that will make sense and reassure her. I agree with you that the more involved she is in decisions and planning, as far as she wants to be and it's possible, the better. But that doesn't have to mean her facing dementia square on if you don't think it would be kind.
For my Dad, he realized something wasn't quite right with his thinking. To make him feel better, I told him that is common for those of us who are aging, that we cannot remember some things. It's like all the file drawers in our brain are over flowing with information, so it just takes longer to find what we are looking for. Sometimes the information will pop up at midnight. Or times the info was misfiled and we just can't find it.