How do alcoholics not get alcohol poisoning?

I was celebrating my birthday I went on an all weekend bender and ended up in the hospital by Monday with severe alcohol poisoning/ withdrawal I’ve been in here for four days now I rather cut my legs off then go through that again the pain, the withdrawal symptoms were excruciating I took a few shots to numb the symptoms before going to the hospital thinking I could tough it out but it only kept getting worse . How do alcoholics do this daily and seem to be functioning as well ?