My village council had a meeting last week with many other villages from the surrounding area in Roi Et Province to discuss this terrible yabba epidemic. My wife was invited and as you say, this problem is huge throughout Isaan and probably same the whole country.
That said, my immediate concern is for my wife's 40 year old brother. Their older brother dropped dead around 3 years ago after years of alcohol abuse. The younger brother, 40 with a 12 year old son, is obviously heading in the same direction. Although he has a good job, he is on the white whisky at every opportunity and on Sunday, his day off, he and his drinking buddies start at 7.30 am. I have expressed concern with other family members but they don't seem concerned that the 12 year old nephew will follow his Dad's example but I can't see him ever getting a job so will only work rice -- and drink white whisky.
In my 23 years with this family I can only claim credit for helping to straighten one young man many years ago. He is also around 40 and working/living north Bangkok with a lovely wife and baby. When he visits the village he always makes a beeline for me as he remembers our heated exchanges from that long time ago and appreciates how he recovered.
So, one out of two is half but I cannot think of a solution to the yabba problem which some say can be bought from 5 thb to 50 per tab. I suppose the price varies with demand and availability.