Your post is tough to answer.

We would be better able to understand your situation if we knew more about you. How old are you? How severe the diabetes before treatment?
How do you manage it..what drugs you use?

Just because you have diabetes, should not be taken to exclusion of something else going on with you. Low B12 levels, low thyroid, exposure to chemicals,
etc. Have you been tested for autoimmune disease markers?

Neuropathy in diabetes can take many years to develop. I have seen diabetics who for 10-15 yrs don't have any symptoms.

Not sleeping, leads to more pain. And I don't think drugs do much for neuropathy, like Cymbalta. They do not reverse it, and only sometimes control pain.

What drugs do you take? opiates? These themselves can cause depression.

So please provide more information here. The more proactive you become in your own behalf, the more likely you will see some improvements.