It's sad you had to lose a toe and part of a finger. What sort of HbA1c s have you had in recent years?
It's damage done by too much circulating glucose, which is often a cause of this type of problem. It's a pity, that you were not put onto an aggressive blood sugar control programme. that might well be your route to avoiding further amputations.
If you can keep your BG at non-diabetic levels, your system has a chance to heal. You need to aim for the 4.7 which is normal non-diabetic BG.
It can be done , either by aggressive use of insulin. I would ask for a pump in your circumstances. or by severe carb restriction. ANd frequent monitoring