@albiet, by mental issues do you mean foggy thinking or confusion? That may be a side effect of the medication you are taking. I only have numbness with my PN so do not take any medications but I have had times where I was pretty down mentally due to the neuropathy. What has helped me is just trying to take things one day at a time and focus on things that make me happy - not that I'm always able to do that but I make an attempt.

There is a book by Norman Doidge, M.D. - "The Brain's Way of Healing" that talks about a way to train the brain (my words) to help reduce or remove chronic pain. I started reading it but never finished and gave it to a friend. The chapters I did read made a lot of sense. He has a website with some frequently asked questions that may be helpful - http://www.normandoidge.com/?page_id=1052