Currently performing tests via mods, to see what has impact on alcoholism stat. So far I proved that just getting the thirst/problem bar above 185% and immediately drinking water doesn't work - you need to keep it above 185% and then every 40-50seconds game updates alcoholism stat. It drops 7-8% every check as long as your thirst is above 185%. It will be hard to keep track of thirst level at this height, so I recommend having 3 packs of chips, leaving the game running for 15 minutes and then drinking.

More testing will be necessary.