@wctdoc1943 thank you for this post. Sorry I disappeared from the community for a bit. Everything that you wrote resonates with me. Let me respond to your questions:
Are you observing significant short term memory lapses, changes in her language function, repeating herself? YES - absolutely. This seems to be dynamic. Every day is different and sometimes it changes throughout the day.

Has she gotten lost while driving or had minor accidents? Most likely because there are long time lapses between when she leaves and returns and most often she says she is going to one place that is nearby. Fortunately, she is not driving much these days. I believe she is aware that something is not quite right and this is why she will stay home all the time. Plus and minuses there.

Is she able to manage finances (keep up with bank balances, pay bills on time)? Maybe. She's old school - so she still writes check for a couple of bills and mails them at the post office. My father has always managed the finances. Before dementia - she was not good with money management. I have noticed a pattern of anxiety with anything financial - anything with numbers (review anything or even conversations related to finances).

Does she do grocery shopping and make appropriate purchases? Dad does all the grocery shopping. She has always loved to shop. This has always been a coping mechanism for her. It is a problem now with dementia because she is aware (I think) of her illness and her shortcomings now and will shop as an escape. This is my own thinking here though and a pattern that I am recognizing.

Is she able to follow a recipe or cook a meal? A recipe- probably not. She will make what she remembers to make - which often is the same thing over and over again. The meal will be simple and not sufficient though - we help to supplement. For example, she'll just make a salad or just make a protein. She is not really able to consistently create balanced meals. She'll just grab things to heat up that are not appropriate for breakfast, for example. But this is not all the time. On a really good day - she pulls together a great meal independently - but then she is completely wiped out after that. She has a fixation with chopping (honestly scares me a bit because unlike many folks have shared on here - she is NOT sleeping)- although it's not as bad as it was say a year ago. Last year, she would chop everything at once - onions, carrots, peppers, tomatoes (some of which you'd chop as needed). We'd realize everything was chopped and we'd have to rush to use/eat things quickly. Now it is just carrots thankfully. 🙂

I love that you offered "Some patients with dementia are aware of their cognitive loss and fret about it. Others are either unaware or are in total denial, despite the evidence." I think she is a mix of all of these. Again, it depends on the day but overall - she's typically angry and combative which is very difficult for me and dad because we cannot get a solid plan for how to support her more routinely. Most often, she'll blow up at us over things we try to help with (because help is required, for example, with her dog) and when we try to talk about things together - she'll leave the room, go outside away from us, or previously leave in her car (this is not occurring now thankfully).