I wonder if you have shingles pain. This can affect the dorsal root ganglia along the spine.
If you had chicken pox as child, it is a possibility. There is a special MRI that will show this:
http://neurotalk.psychcentral.com/thread147771.html
This thread explains the test, and also what the dorsal root ganglia are. Once damaged, they send signals to the brain which are often phantom in origin. Some people do not genetically have the capacity to heal injury to this nerve bundle that is outside the spinal cord, along the vertabrae. So a chronic pain condition develops.
Placing Lidoderm patches along the spine can often turn off some of this pain. Sounds like it is a thoracic area problem.
At least if you have a diagnosis your doctors would be satisfied as to your continued pain management I would think.
Typically diabetics can be low in magnesium, as they lose it thru the urine, daily, for some unknown reason. So taking some magnesium supplements, may help this. Use a chelate and aim for 1/2 the RDA, which is about 200mg elemental.
Oxide form does not work.
This is my magnesium thread:
http://neurotalk.psychcentral.com/thread1138.html
We've had some posters on our Peripheral Neuropathy forum, have a reduction in pain, when using magnesium properly. You can also choose to eat foods high in this critically needed mineral.
You could also be low in B12 and Vit D...so getting tested for that may reveal a way to lower your discomfort with supplements.
This is our PN forum:
http://neurotalk.psychcentral.com/forum20.html
There is alot of information posted on that forum that we have collected over the years. Most doctors have no clue about it either.