My cousin drank herself to death. Took 2 years. She had Crohn's disease and was in the end stage of the disease. She had suffered since in her late 20s with countless operations and lots of physical pain. Anyway, over the course of her disease, she developed an addiction to pain meds because she needed so many just to function. Without sharing details, she got in some trouble and one of the court orders was mandatory weekly drug testing. So, still being in enormous pain and needing to find another way to deal with it, she started drinking excessive amounts of alcohol. She was a tiny thing and was never really a drinker. From the time she started drinking to the time she died, took about 2 years. It wasn't a pleasant death. She died of liver failure, cirrhosis, I guess. To be fair, I'd imagine her liver wasn't in the greatest of shape when she started drinking because of all the drug use over the previous 3 decades. I saw her before she died. She was already unconscious and the yellow color of her skin was indescribable. I've never seen anything like it. Dying from a bad liver is a miserable way to go. My sister died from a failing liver, too, except she had cancer of the liver. She was in excruciating pain for the nearly 2 years she was fighting the cancer until her death, even with all kinds of pain medications.
Of course everyone has to make their own choices in life. I think in order to achieve a relatively quick death with alcohol, you'd have to consume an enormous amount of it that the body will surely try to reject. I know it can happen, as I've seen stories on the news about hazing incidents where a pledge dies from alcohol consumption. I think those are the exceptional cases, though. It doesn't happen that often. I hope you make the best choice for you and can get to your peace no matter how you need to get there.