Aspiring doc has a great idea about the anonymous email... when you get a response, could you please let us know what they say...
I agree with depakote and jochi about not including the alcholism in your application... It's a huge risk to include it in your PS, it will rub some AdComs members the wrong way... you don't want to have readers a reason to toss your application out of bias.
I agree with DayDune in thinking that you shouldn't hide the past, covering it up as immaturity or excessive partying. That seems worse to me. Alcholism is a real medical dilemma and it takes motivation and strength to recover from it... the experience has been a huge learning experience for you so it should not be disguised as something else.
My *non-expert* advice....
Leave the alcoholism issue completely out of your primary and secondary applications. When you're at a medical school for your interview, the alcholism could be brought up by you when an interviewer will ask about your initial low gpa... And you'll be able to convey your experience and what you learned from it MUCH more effectively in person than on paper.
There's a lot of pressure on you at that point, you have to project yourself in a way that convinces AdComs that you'll avoid falling back into substance abuse... the words need to be carefully chosen and impactful. You have to be very clear on what you learned from your experience and what steps you have taken to assure that the recovery is permanent.
Instead of an interviewer thinking "this person has a history of substance abuse, I wonder how he/she will handle the stress of medical school"... they should think..."this person has overcome alcoholism and has accomplished many things as a competitive medical school applicant despite his/her rocky start, this person understands how to overcome a major problem, recuperate successfully thereafter, and learn from it. what an inspirational story!"
I'm personally amazed by your resilency and dedication to have recovered from the addiction. Way to go!
Opinions lie all over the place, do whatever makes you feel comfortable with your application. And don't let anything hinder your aspirations.