Do you think your job carrying mail could have affected your neck? Excessive alcohol can cause neuro damage and also B12 deficiency. But it seems that alcohol abuse is well in your past. Does the neurologist know about your traumatic brain injuries? Do you think they might be relevant? Was your neck involved in the TBI's?

I have had "paresthesias" since 2001, similar to what you describe, and a cause has not been found. I had a positive Lyme test at the time. I gave up dairy and gluten. My neuro is not aggressive. I have diagnosed spinal and neck issues. But unless I want surgery, my neuro avoids ordering imaging. At one point I had an MRI and also EMG testing. If you can find a way to pay, an MRI of your neck and/or brain would be useful I would think, as well as an EMG.

A physical therapist has been most helpful for me, especially one who is good at manual therapy (massage). I find that the PT is better at diagnosing and explaining, than the doctors. I also found an orthopedic doc who is not a surgeon, who was helpful. Pain management might help you too.

It's interesting that for a long time your symptoms would come and go. Your primary care doc could run some tests for autoimmune issues. Your neuro could consider MS-? You could get a Lyme test.

I do tai chi which helps a lot, not sure why. I have not found real answers in 23 years but hope you do!