My sister-in-law had a lot of the same issues you describe. Originally, they thought mg, but eventually decided it wasn't mg. After several more months of slowly degenerating symptoms, she was diagnosed with ALS (Lou Gehrig's disease). I know that isn't a good diagnosis for anyone, but at least they finally got it right and she was able to get the assistance she needs. As she says, the uncertainly was killing her all by itself. Obviously, I'm not a doctor and am not trying to diagnosis you. I'm simply giving you another direction to look at and research.

You will be in my prayers that you will find the diagnosis and help you need.