What if all the treatments for peripheral neuropathy don't work, what then? Is there still hope?

Treatment. I'm not sure what treatment you received before. The treatment of peripheral neuropathy depends mainly on the causes. Some of the treatment including physical therapy, medications such as anti-seizures, antidepressants, topical cream, injections such as nerve block, spinal cord stimulation. Please see a pain specialist for evaluation. Spinal cord stimulation seems effective in many cases.
There's always hope. Without knowing what caused the problem, but assuming that treatments have been mostly pills, there are treatments involving nerve blocks, procedures for chronic pain including spinal cord stimulators, desensitization techniques, even biofeedback. Find a doctor who won't quit trying, like a physiatrist or pain management specialist.