Cocaine and alchohol together is a dangerous mix. My ex did the same every week. Once a week ritual for him, and he'd get fidgety if he didn't.
He hated it and loved it at the same time.
Unfortunately, he has to want to stop. A lot of people take it now, and it's more socially acceptable in large groups. I've seen it.
I tried everything for years. Begging, pleading, crying, threats. All in vain.
Although there aren't any real physical withdrawals from what i understand, it's all mental.
And like your ex, he would become verbally aggressive under the influence. He thought no one has a right to complain about anything.
It all sounds familiar? The only advise i can give is to do your own thing, with your own friends, your own family, and have a life separate from his. It's easier to let go that way and move on.
But the obsessing over him will take time to go. I still worry about my ex even now.
Limiya