Sex File: What should I do about my husband's lost sex drive?

It sounds like your husband feels impotent in every sense of the word. He feels that he has failed you and he can't see a way through, so he has withdrawn.
I understand that you find this situation difficult, but I would urge you to take a step back and think about what your husband has been dealing with. He has had to adjust to the shock of a diagnosis that can be managed but not cured. He has also experienced complications that any man would find challenging - one in three people with diabetes experience sexual difficulties,