A neurologist is NOT the best doctor to help with nerve pain. Even so-called MS specialists lack the knowledge, skills, and experience required to properly and thoroughly deal with nerve pain.
Having a consultation with a "pain management" doctor, usually an anesthesiologist with advanced training, is a MUST -- ask for a referral; most insurances do cover pain management (and second opinions of pain management doctors).
For many types of nerve pain, there are procedures available, such as pain control injections, Baclofen/pain pumps, and more. While a pain management specialist can tell a patient if *medically necessary* prescription narcotics will help/stop the patient's pain, most pain management doctors won't prescribe them and will instead send the patient back to their primary doctor for meds such as Oxycontin, Oxycodone, methadone, morphine, etc.
Bruce, get your wife to a pain management specialist ASAP; one shot in her arm will take away her pain, and the effects from the pain control med(s) in the injection can last for several months.
Best of luck everyone.