Have you had a full autoimmune work up? Celiac runs in families and it can go straight to neurological problems with out digestive issues.
My full body neuropathy also started with horrific neck pain that I woke up with one morning and couldn't move my neck. With in 2 months it spread through out my body. So in cases like ours, I believe something was underlying and the final straw just put the nervous system into a crisis. I also was very strong, worked out every day and was happy. Don't know what the hell happened.
Be careful dulling the sensations with alcohol- you could have a metabolic issue that is causing the nerve damage and alcohol is a neurotoxin....believe me, I wish I could have a glass of wine, but I can't anymore.
I recommend going to an endocrinologist, and a rheumatoligst. Maybe even an infectious disease doc.
With out checking for genetic mutations and no family history of this, saying its genetic is useless and unfounded.
If your daughter has autoimmune diseases that would be the more likely path to follow once something structurally wrong is ruled out. Autoimmunity hits at any time, any age and runs in families. It can be triggered by a virus, or environmental exposure or pathogen. The thing about autoimmunity in families is that one will have ms, one will have crohns, one will have RA... and so on. It doesn't manifest in the same condition per say.