Diabetes can cause problems with the peripheral nervous system. My aunt has peripheral neuropathy, which means that the nerves in her extremities have been damaged, but her central nervous system is fine.
She had tingling and numbness in her legs, feet, hands, and arms. Sometimes, she could feel pain in them, but they hardly ever felt normal.
It sounds strange, but her doctor actually prescribed an antidepressant to treat her peripheral neuropathy. Somehow, it is able to fix the problem.