@bigfatdoormat, you have much less of an alcohol problem than your husband. Please don't let these catastrophising replies nudge you towards thinking 'in for a penny, in for a pound'. You evidently are managing your drinking, though dependent on it.
Your husband, sadly, has let his addiction get control of him. What you describe is a very serious dependency, to the point where going cold turkey could be risky (if he could even do it). Were he to choose sobriety, a first step would be to consult his doctor about a detox.
This must have been a dreadful shock. Don't use it as an excuse for a few extra drinks to get over it! You can't control or cure another person's addiction - look up the "three C's" for more on this. A couple more "C's", which you'll encounter if you join a recovery programme, are:
Don't conceal it. Let him know that you and DD have found his stashes.
Don't contribute to it. This includes doing stuff he's not taking care of because of his drinking.
When you tell him you know, he's likely to experience immense shame. He will feel trapped and may become angry and/or try to blame you. Another common response to the shame is an immediate promise to get help. Support this if he does it, but do not expect it or take responsibility for his recovery (you can't cure him). Addiction makes liars of us all.
Meanwhile for you, I'll just recommend alternating your glasses of wine with water, tea, cola - anything wet and non-alcoholic. This useful habit makes your wine last twice as long and keeps you hydrated..