Update: I'm still not regretting my words, and have become more confident that my sugar intake plays a very big part in my PN.
When I was diagnosed with PN, I was still drinking alcohol. I tried two times to quit, and both times I failed after about 40 to 50 days. What happened was that in the first two weeks, my PN improved dramatically. I expected that to last, but to my surprise the pain slowly came back and reached the same levels as when I was still drinking. This was very discouraging and broke my resolve to stay alcohol free.
After begging my doc for a referral to a rehab center in May last year, I successfully quit after spending 70 days there. Again, in the first weeks the PN clearly improved, and I was even able to play some sports again. Yet, by November, I was again in pain and agony, and really didn't understand what was happening. My B12 levels had been high enough using weekly and then monthly injections, I had taken a B-vitamin compound three times a day, not a drop of alcohol, and still.
I would have understood if the pain stayed at the level it was after three weeks (bearable), as the wisdom was that PN can not be cured. But I didn't understand the brutal relapse. It made no sense.
Of course, in hindsight, what I started doing when I got sober was consuming large amounts of sugar. (when I was still drinking I consumed large amounts of water for most of the day...). Somehow this doesn't show up on the blood results - my liver values became excellent - except for one thing: the high LDL levels on my last test. Higher than they had ever been while still drinking alcohol, and despite eating rather healthily (fresh food & home cooking most of the time). The only logical culprit of both my LDL levels and my continued pain was perhaps to be found in the 2 litres of high sugar soda and vast amounts of sugery snacks per day?
As soon as I stopped doing both, my pain started to subside, and, what's more, my energy level improved substantially. Also, without watching portions, but including more fiber and holding back on carbohydrates and especially sugar, I started to lose weight (this is all happening within the last 3 to 4 weeks).
As I type this, there is no burning, no zapping, no cramps. Yes, my feet feel "tired", and my toes are still a bit over-sensitive. I still have good days & bad days. But... my feet are starting to sweat again (?!). Walking around actually *reduces* that tired feeling - whereas before it only made the pain worse.
I'm not saying it's all down to the sugar. Having restored my B12, B1, and D3 levels most probably plays a big role. I might start to cut down on the other supplements like Acetyl L-Carnitine and CoQ10 once I finished those bottles, and see what that does. I will continue to use topical magnesium, but may cut back on the oral version, and instead will eat enough fiber to get it in a more "natural" way. I will also continue to take the krill (omega3), as I'm allergic to most fish, and continue with the R-lipoic acid for now.
Will report back when appropriate, but I want to thank this forum (and yes, a special mention should go out to Mrs D.

) for giving me the information and the will/motivation to keep on searching. I may be a very "lucky" guy in that I seem to have found my way out, but I think the service you do to all of us is absolutely
invaluable.
And to the docs who just tell us "
it's pain, there's no cure, live with it": please reconsider your attitude. You have
no idea how much damage your opinion does to people who are already on the brink due to the excruciating pains they have to live with.
Thanks for reading.