Take her out for the day ( when she's sober) and make the day erally special. Tell her that you love ehr and because of this you need her to address her drinking problem and stay pleasant, calm and understanding and ask her why she feels better when she's had a drink.Happy people are generally not alcoholics, so there will be some reason that she's drinking and initially before you or she can do antyhing about the drinking she needs to find out what this is ( sher may not be sure herself).
Once you are openly communicating, start a strategy of reducing drink ( not cutting it out) until it's at a manageable level.Let her know you love her and support her and be available to talk about anything that's bothereing her both current and in the past. Once the reason for the drinking is addressed she'sll start to feel better and less powerless and hopefully will be better able to take control of her actions. I'm going to say avoid AA like the plague and risk getting my head bitten off by people who think it's wonderful, but AA disempowers the individual and works on the belief that once an addict always an addict, and that is not a healthy or helpful mehtod of quitting excessive drinking, nor should total abstinance be necessary if she deals with whatever is bothering her long term.
I was a very heavy drinker and I got control this way and would reccomend it to anyone. Hope this helps.