I didn't read your other posts, at least I don't remember reading them. Just a thought...have you been tested for celiac disease/gluten intolerance? Lots of people only have neuropathy symptoms when gluten is an issue for them.

I am sorry your struggling. I know this is a scary thing to face and with so much unknown. My best advice is to stay in the moment which is super hard I know but I am trying to work on that myself. Unfortunatly Melody is right that it takes time to figure out what is going on. With the proper treatment things can get better though. Do you think maybe going to talk to a therapist may help? I waited to long to see someone and get on proper mental meds. It won't take away your physical but it can help with coping and anxiety around it. Are there things you can do with your current physical limits to lift your spirits? I wish I had more answers for you. I hope you can hold to hope and get relief/answers

The guitly feeling of dragging your better half down doesn't help either. At 46 I broke off my relationship with a lovely lady simply because I knew what was coming. She wouldnt accept it and 3 years later she loves me more than ever.
what Im saying is your stress levels are high since others are relying on you.
This is adding to the PN flares etc. The best advice was in the previous post being "live in the moment" hard to do though.
one thing at a time, tear the mountain down into manageable pieces. Firstly your fiancee would have seen you suffer so she knows, that can be the hardest bit, convincing others. Try to be strong and take the pain whilst with your fiancee. She still needs most of you as you were at least mentally. My partner and I had the best NYE cycling around PHI PHI island Thailand, her in joyous laughter, me in a chronic pain grin.
pain relief first followed by DX. followed by one day at a time. There is no easy way out but there is hope and your still relatively young.