How do you handle the issue of a parent with short term memory loss who downplays it and gets angry if you mention it?

When I first started to notice her forgetting things over a year ago, I would just try to jog her memory. Didn't take long to find out that was not appreciated. That has advanced to remembering things incorrectly and asking the same thing repeatedly. I've learned to just roll with it unless it's something important. I don't call attention to it. She is aware because she mentions it occasionally. But also tries to downplay it and laugh it off. When she mentions it I say " You might want to talk to your doctor about that". I've been working on getting her to a doctor. After hearing less than impressive things she had been telling me about her primary doctor over the years I decided I wanted to try to get her to a new one that was also closer to where both of us live. She agreed. Finally found an office. Her first appointment was supposed to be last month. Despite reminders the day before, when I checked on her she was on her way to the store. It's rescheduled for tomorrow. I've spoken to them in advance about the issues she is having. She doesn't know that. I'm pretty certain she would resist going if she did. I told her yesterday that since I am going to be off for an appointment too, I would come by and take her to her appointment and then we can go to lunch. I have never taken her to an appointment before so she seemed a little suspicious about it. She said "They're going to think I must be a real basket case needing my daughter to come with me." I'm not sure how this is going to go. I don't think she will want me to go in the exam room with her. So I won't know what kind of answers she gives the doctor. She apparently hasn't listed me as someone who can have access to her medical info yet. So I'll probably have to try to convince her to do that while we're there. I'm her only child and she's divorced so, there's no one else. I'm afraid she is going to fight getting help all the way because she fears finding out what might be happening to her. I would be scared too. I'm really worried about her. Right now she is still able to take care of herself. But I keep thinking what if she leaves the house one day and forgets where she lives. She told me I was born in 1994 the other day which is about 20 years off. Any thoughts or tips about this are greatly appreciated!