Why am I second-guessing myself asking if my mom is really that bad?

I talked with mom's doctor today about the mental declines (or stubbornness?)I've seen lately and she's going to have her see a neurologist for evaluation, saying that based on what I've told her, Mom should definitely be in ALF or NH. Now I read an email she (mom) sent (yes most days she can do it fine) and it's concise and mentally fine sounding. So I wonder - am I just so frustrated that I'm exaggerating things in my mind? She still lives alone next door to me and does function as long as there aren't glitches in her world. She goes to a Christmas parade and drives a golf cart on a state highway to get there, but then I think, 'well it was only about a mile away, and we are in a rural area', then I remember the semi-trucks that speed down the road and the 2 accidents we've seen in front of our home -in the last one a wrecker had to pull the car out of a tree. I waver between worrying and wondering if I should be worrying at all. I guess part of it, too, is that Mom's NPD with flavors of BPD. One doctor thought she may have MPD --- which only means that I feel guilty as anything if I make any negative comment about her. I'm not supposed to "tell on her." So the guilt makes me wonder if I'm really seeing what I think I'm seeing. Maybe it's not all that bad??? Will the neurologist clarify things for me?