I lost 25 kilo's over the course of 2 years, and if I eat 20 grams of carbs in one sitting, I will spike. So I just have 20 grams or less a day. (If I went for 100 grams a day, my numbers would be horrid). From what I understand, insulin resistance can improve a little with weight loss, but reverse entirely...? Not that I know of... The weight most likely came on because of insulin resistance, after all, before it crossed the threshhold into T2 territory. It was there before the weight, in other words.
You could try going lower carb, into keto? Only mentioning it because of the neuropathy, as it's not for everyone.