Sounds like you are having a really difficult time. I am only on month 6 and already extremely frustrated, so I can only imagine how I would feel after years of this.

My physiatry clinic is specifically for neck and back pain. The physiatrists evaluate your symptoms, range of motion, etc. and then prescribe an exercise program that very gradually increases strength. I go twice a week and work out with a PT or rehab specialist. My particular clinic has specialized weight equipment that very specifically isolates the muscles on either side of the spine. I just started a couple weeks ago and WARNING: it feels worse before it feels better. Apparently this is not uncommon, but my clinic reports that 2/3 of people who complete the 9-12 week program do not need to seek medical attention for back pain again.

As I understand it, the major difference between this and chiropractic is that a chiropractor manually adjusts the bones of the spine. It can be a good complement to muscle strengthening as it correctly aligns the spine so the muscles are holding it in the proper position.

Not sure about the difference between physiatry and orthopedics.

Also wondering if you have contacted your local Brain Injury Association. Mine provides referrals to brain injury clinics, where they might have a variety of different types of rehab.

Hope you're able to find some solutions and/or peace soon.