Hi there,
I am a am alcoholic (4 years sober) and it took me an a firm ultimatium to stop drinking. I can't have just one drink... It's always been like that for me so it was all or nothing. In the end I was going to lose everyone important and special to me and I made the decision (after a huge binge that lasted 3 days I might add) that I wanted my life with the people I loved and could do without the drinking.
It was a hard road and I did it cold turkey, no AA or anything like that, just family and my boyfriend of the time to listen and help when I was feeling low.
I still to this day would like to get drunk (having recently broken up with my other half - I'm at my lowest point) but it wll solve nothing.
Tell her that you are wanting her to stop because you love her and want her life to get better. It's a hard road but you have to be firm, if she trusts you then you are half way there.
Good luck
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How I describe myself:
Honest, caring, trustworthy, reliable and generous.