Chances are she already knows about your drinking Galumphus. As much as we like to think it's a secret, it's nearly impossible to drink that much without our spouses or significant other knowing. More likely she's simply in denial about it. And quite frankly, if you don't do something about your marriage will probably end eventually anyway.
If you fear you'l have physical withdrawals, you need to see a doctor. Doing it on your own is potentially far too dangerous without at least an initial consultation. Detox and rehab isn't inevitable, but don't rule it out as a possiblity.