They drink often, yes, but they don't get wasted everyday. I'm not saying that's a good habit, but that's not gonna put her in a grave at a fast pace. If all the people who drinks like her would be dead by their 40s or 50s we wouldn't have to finance retirements. Also, who gives a shit at what hour they drink ? If alcohol is a problem, there is no "good hour" to drink.
I'm not saying that they have a healthy way of life, but you saying "This girl is fast becoming dangerous to herself" is excessive. If she was dead wasted 3 days every week, I'd say you are right. But what I see them doing is nothing that I did not saw in my younger days. And the friends who were indulging in this kind of excess had to go to class or work the next day. They are all still alive (at least those I'm still in touch with) and most of them are leaving a healthier life, are in a relationship and have kids.
Damn, now that you make me think of it, they all turned pretty good in the end. I would not have bet money on that, at that time.