Yep, I'd get the shakes and drank daily to keep them at bay, but a combination of self-directed weaning-off and benzodiazepine sedatives saw me through. I never got so bad that withdrawal would have killed me (don't think so anyway), but I definitely saw that writing on the wall. I can't speak for those who've consumed a half gallon of vodka every day for years, but my belief is that it's not so much that they can't stop but rather that they simply don't know how to navigate the process. More-so ignorance than physical inability, assuming they actually want to stop. I understood the mechanisms at play well enough to obtain what I needed and self-medicate but many don't really possess a working understanding of pharmacodynamics and neurochemistry or how to manipulate it, so they usually need some help.