When did you realize it was too much? Number of drinks? Hangovers? What was "heavily" 3/4 nights a week? What precisely was the moment you were brought to your knees as you say?
"Realizing it" happens gradually after an established pattern of behavior. Usually, years. You're like, I seem to drink a lot more than everyone else and maybe that's not good. Eventually other problems kick in like sleep issues, anxiety, possibly weight gain - and the solution is always drinking because you stop worrying about it, or can at least say "well this is one of the last times." You realize that this is a bigger issue and then decide to stop, but something inevitably draws you back in. There's always something. And since you slipped back in, you somehow find your way to drinking as much or even more than you did. And then you realize the issue is even bigger - you've established a pattern of trying to stop and it never sticks, no matter how sincere you were in that moment of decision. No matter how much you poured down the drain. No matter how much you know that being sober is actually the good life and that your problems are much easier managed when staying away from drinking.
And after many attempts of this, trying and failing, but probably knowing that deep down there's a part of you that doesn't want to stop, you hit a point where you feel the worst you've ever felt in your life, hurt someone, or instigated another serious problem. And if you're honest, you know where it all started.
Then you are on your knees. Some people try to fix the problem themselves in earnest, some seek help, some stay in the cycle and break out down the road, and some stay in until the (statistically early) end.
Hangovers turn into waking up drunk at some point. For me, they were a reason to drink. Withdrawal is like a hangover that lasts for weeks. The whole time, you will want a drink.
My bottom was the realization that my alcoholism was a way of checking out of my life. Once I realized that, I just had to start doing other things and dealing with the problems I tried to drown.
When you are in the pit of addiction, the first things you need are positive alternatives to drinking. It could be AA but I went a different route. I am not a meticulous scheduler, but I had a rigid schedule for the first few months. I even planned out my free time. I put myself back out into the world, and found that I loved it and the people in it.
I'll be a year sober next month.