Is there some sort of state program or perhaps some other type of insurance to which your doctor is referring? Looking at http://seniortransportation.easterseals.com/site/DocServer/NC_Physician_s_Guide.linked.pdf?docID=142652, it states "In North Carolina,
physicians are not required to refer their patients for driver medical evaluation. However, NorthCarolina physicians may perhaps be confronted with a legal as well as an ethical dilemma if they have expert knowledge of a patient's medical condition that may be hazardous for driving. While no North Carolina physician has yet been convicted of a criminal offense or successfully sued for failing to report a medically unfit driver, case law in other states has supported an obligation to refer medically unfit drivers for evaluation"
So there'd be some duty on the part of the doctor to report you if she noted in your log or medical history or in some other manner a situation where your management represents a hazard. It appears very low risk for the doctor but, if you drove through a crowd of people or something like that, to the extent that your medical history might be investigated, a plaintiff could perhaps work to "go after" the doctor so the doctor may be prudent and ethical by protecting others if she feels you are a risk.
This probably would not qualify you for SSDI, or federal disability benefits, since they ask different questions like "can you do anything?" At least one Supreme Court justice probably wouldn't buy an argument that you are disabled in that sense.
Diabetes is very challenging but if your doc is taking steps to get your license pulled or restricted, it may be worth taking up the challenge to get your numbers where they need to be. You may also be personally liable for any damages you cause should you injure anyone with a car while you're zonked out.