As i re-read your first post i see that you DID try a patch (Lidoderm). I am referring to the Fentanyl patch.....very powerful opioid. They come in all doses. Maybe your doc would be open to try you on it. It helped me to say to the doc that "My pharmacist said to ask you...." Some docs don't like to be flatout asked for opioids. But you truly are suffering and that's what the dang meds are FOR. I hate uptight docs when it comes to pain....
Another thing, some of my issues are 'female' related .....hormones and such....
feel free to send me a PM and we can talk on more of a girlie level without the world wide web reading......
Also, consider asking about glucose levels and metabolic neuropathy......they play an important role in finding the underlying cause so hopefully not to have to take strong meds for too long.......
At first i 'poo-pooed' those terms, but turns out they may be right up my alley....

Truly caring....
Rae