how much alcohol is lethal?

I can't get a straight answer to this. Of course I realize everyone is different but there must be some idea. For example, after a period of abstinence I drank over the course of 10 hrs, eating ample food, about 10 shots of vodka or 2 fifths (at least I think the bottles were fifths, can't work this out and have no one to ask---they were the smallest Smirnoff that wasn't a miniature). Appreciate any help. Am trying to stay sober, very scared of my tendency to drink---been happening since 16 yrs old, now 55, nearly killed myself in ODs with it several times. Mostly don't drink, have been in AA since 25, mostly sober for long periods of time. Am also bipolar and tend to relapse when depressed to lift my spirits or when manic to calm them. Thanks.

it depends on the body weight, one's metabalism, and amount based on the time drinking. so everyone's different.
glad you're sober. i get in depressed states with my bipolar and double up on therapy appointments. also see my pdoc to tweak or up my meds to get me out of the funk quicker. that's allowed me continuous sobriety. course accepting i am an alcoholic and going to AA has helped me the most.
a side note-alcohol is a depressant so it's not a good fit for coming out of depression. it only adds to it.