Hi Danboy,
I don't know about Ritalin for fatigue. Intuitively it Seems like it could be a potential misadventure. Our nervous systems are already haywire so adding on stimulation is maybe not so great.
Have you had your Vit B and D levels checked? These are commonly low in folks with chronic pain and nerve conditions and can lead to a lot of problems overall if unaddressed.
For me the biggest helpers are a diet that is as clean and nutrient dense as possible, Daily vitamins and anti-oxidants and exercise. There is always some level of activity that can be done. Even a tiny bit of exercise is helpful. When I was completely unable to bear weight I would get in a nearby pool and swish around with a buoyancy belt. It made a big difference in my strength and morale.
Keep up the fight!