I speak from the perspective of someone in recovery and an ACOA. Dad had his battle with alcohol over a four year period (ironically almost the exact length of time I struggled). I was an adolescent/early teen during those years. Over thirty years later it is crystal clear now that his primary issue was actually that he was an untreated manic depressive-wild spending binges, huge personality swings, etc, etc. I know it sounds terrible but as awful as I was while I was drinking those particular things I did not repeat btw. I remember doing EVERYTHING I could-pouring out booze only to have him buy more, rationalizing, begging, you name it. You would think that as those in recovery we would know better what a futile exercise trying to control an alcoholic is, its like trying to herd cats (bad joke). As so many advised our loved ones, give as much support as you can to the daughter. Take her to Al-Anon or Alateen meetings if she's amenable, find online support groups to direct her to. Acknowledge your anger. Set your own boundaries with your friend, if you know she's drinking and driving then let her know if necessary you will provide her liscense plate to police if this is an approach you're comfortable with. Decide whether this friendship is helpful or not to your own recovery and then, BREATHE, and let go. I know letting go is the HARDEST thing in the world but truly as a teen I drove myself crazy over behavior I simply could not.
Peace,
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