Sorry scifigal :-/
Maybe it's time to consider medical marijuana for pain relief? Or you can try one of the few non-opioid, non-NSAID painkillers out there: en.wikipedia.org/wiki/Flupirtine
It's not side-effect free, but then what is?
As for withdrawal, it absolutely sucks. Not much you can do except ride it out, although the worst part is over with relatively quickly (4-5 days). After that it's far more bearable.