Neuropathic or nerve pain can be difficult to treat thats for sure and treatment recommendations differ between doctors and between different kinds of pain. The link below provides several different alternatives.
http://www.uspharmacist.com/oldformat.asp?url=newlook/files/feat/jun00pain.htm
On the bright side there is a huge market for a really good neuropathic inhibitor when one shows up. Lyrica was a step forward and its unfortunate its not working in your partner. Pharmaceutical companies are well aware of that and are avidly looking for more answers. The article below also mentions some other options.
http://biopsychiatry.com/bigpharma/neuropathic.html
Good luck