It really is down to the luck of the draw on how long alcoholic's live my Grandad died at 78 years of age and Drank nothing but Guinness for over 50 years, he was drink driving for most of them and somehow never got caught, he survived heart attacks and strokes due to his drinking and eventually died from Alcohol related Dementia. He probably got a few more years than he should as he lived in a home for the last 15 years of his life which slowed down his drinking a bit but he never stopped until the Dementia took hold at the back end. My Uncle is pushing 70 and he still drinks like a fish and his liver must be shot as he is turning yellow now.
On the other hand my Cousin who was also an Alcoholic and Drank to excess was found dead at 25 years of age due to his drinking and i knew another lad who was an Alcoholic and Died at 24, he drank and managed to stop but then suddenly restarted on a drinking session that lasted a week and he died by choking on his vomit as he tried to drink to the levels he previously had and his body couldn't take it.
I have just turned 33 and i've also had issues with Alcohol and to be honest don't know how i have survived as i often drank between 50 and 70 pints a week or drink up to 7 litres of Cider in a session, i could go days without a drink but would then drink between 30 and 50 units a session and pass out drunk. I have ended up in Hospital, lost Jobs etc due to my Drinking and almost died on several occasions as often i would drink the equivalent of a litre of Vodka in one or two hours and collapse as my body couldn't take the abuse, i have coughed up blood and all sorts but i never died and i did this for years at a time. I'm ashamed of a lot of the things i did when drinking, thankfully i'm sober at the moment and have been for well over a year apart from a one day binge last September were i ended up in a mess again, thankfully life is better Sober than Drunk but i know i could slip back into old habits very easily as i have done before, i just pray i don't.