This is a somewhat disparaging term used in AA for attempting to quit an addictive pattern without joining a twelve step program or attempting an analogous thing to achieve personal growth.
In essence, the individual will still function as a broken individual with the same faults and foibles and fucked-up-edness which made them toxic to be around before they stopped drinking but their unpleasantness will actually be more apparent because they are lacking in whatever substance/behavior made them pretend to cope.
Prone to relapse; it is hard to get a grip when you're white-knuckling it.