For all I know, it's only a story, and it might not be useful to you in any case...but a young fellow lost the flesh from the bottom of, at least, one foot.
One large callous formed.
He applied pure, therapeutic grade, lavender oil, repeatedly. The callous turned to new flesh.
It couldn't hurt.
I would choose the lavender oil from Young Living Essential Oils.
Also, I would also eliminate all possible toxins, including anti-persperants, and laundry detergents.
That will be a major task, I know, but maybe something there is interfering with your well-being.
You could make a list of your changes and any effects. Then, later, you can test for any return of symptoms as you take things back one at a time.
Maybe there is a magnesium/mineral/lavender foot rub, soak, or bath that would help. We've seen good things from the one we have. It is mixed by a local fellow.