Its all individual.
In 1998-99 I was drinking a quart (or more) of vodka a day to self medicate for the pain and became dependent on alcohol.
In 2000 when I was Dx'd with PN - I stopped- cold turkey.
No AA. No groups. Just stopped.
Stayed off for 5 years except at New Year's eve - 1 glass of champagne or my birthday- one drink- beer or wine.
Now, I like a beer or wine with dinner - one beer, on occasion.
Last nite I had brats with sauerkraut & a beer - one.
My neuro looked at my drinking history and pronounced alcoholic PN.
Some tests, skin biopsy,etc.- the Dx stuck.
I think it was B12 deficiency prior to the drinking (and the drinking made it worse, but I didn't know that at the time), but........ that's life.