My best suggestion is just giving her honesty & being prepared for it to be many, MANY conversations.... not just one. I've always found that DD needed time to think & marinate on the things we talked about, and that it always left her with more questions later. It was important that she understood I truly meant it when I said that I had an open door policy for her to ask anything. Sometimes the only answer I had was, "I need some time to think about that really great question you just asked..." and then I made sure I DID get back to her, and not just brush it off.
I had to remind her that me being honest meant that sometimes that answer really WAS "I don't know". Not because I'm trying to avoid, but because I was navigating new waters too & didn't always know the way myself. I could promise to come back to her when I had it more figured out, lol. I also showed her that I didn't always have my crap together in all of this either -that it took me off guard at times & it was normal for her to feel that way too.
We talk about addiction as a whole, not just related to RAH & alcohol. We talk about drugs, gambling, sex, food - any kind of numbing behavior that can be used to hide or filter emotions.... how on some level, we are ALL broken.
We talk as openly about recovery as we do addiction.... & how so many people are affected more than we can see on the surface - I can't tell you how many times DD has been able to be there for other kids at school or in a club when crisis occurs in their worlds, just by listening & letting them know that they aren't alone.
We watched a few episodes of Intervention together, ones that I had previewed & felt she could relate to her own situation.
I had to own my side of the street in all of this and explain how my own codie behaviors were often as bad if not worse than his addicted behaviors. I explained how hard it was for me as an adult to be un-learning all of this & trying to put better behaviors into practice in my relationships. I call myself out when I fumble on it & explain what I did "wrong" & how I was correcting it.
One of my favorite tricks has always been turning her questions around on her - what was your first thought when you saw x, y, z? How did it make you FEEL? Did your stomach roll, etc?
At this age, I've also shared MANY pics of DUI accidents & the details of injury & death that result from it. I do NOT take drinking & driving lightly.... I don't EVER want her to accept the possibility of getting into a car as "it'll be alright this one time" instead of knowing that "No is a complete sentence & the only reason I need".
We've talked about things like date rape drugs & how college girls are showing scary trends of binge drinking. In middle school DD is running into real-life examples of early drug & alcohol use every single day. It blows my mind that the school flips out if a kid has aspirin in their bag for headaches, but they can smuggle vodka-laced gummy bears in without raising a single eyebrow.