Hey man,
First of all -- WELCOME. Sitting in your car sucks, but the fact that you found us is a really good thing. There are people here who have been through what you're going through, both regarding their own addiction and a spouse's or parent's or child's alcoholism.
Secondly: Think back to when you were an addict. Was there anyone other than yourself you could blame for becoming an addict? Was it somebody else's fault that you did cocaine and got addicted?
I'm asking because you sound like you are on some level blaming yourself -- you say your emotional affair triggered your wife's alcoholism.
Here's how I see it: You had an emotional affair. That was a betrayal to her. Guess how many people in the world deal with stuff like that without starting to drink? Just among my friends, I can count three friends whose spouses have had affairs of some kind just this year. None of them chose to deal with it by drinking.
That doesn't make them "better" than your wife. It makes them healthier. And whatever excuses your wife has for her drinking, the truth (which you know, as a recovering addict) is that she drinks because she is an alcoholic. A non-alcoholic might get drunk off their arse if they're sad or hurt or feel betrayed -- but someone who's not an alcoholic doesn't get up and start drinking again the next morning. And the next. And the next.
So please. Stop taking the bait. Stop taking the blame she tries to lay on you. I was the reason my ex drank, too, if you believe him. Forget the fact that he had been drinking daily for 20 years when we met. Forget the fact that he hid his drinking successfully from me until I was pregnant with our first child. In his mind, he drank because -- and you can pick your reason, it was a different one every day. I was fat, I was ugly, I couldn't cook, I had looked at him sideways. Or his boss had. Or the bank teller had.
Drop. The. Guilt.
She is an adult. She is responsible for her choices, and you are responsible for yours. Another thing I've learned here is that alcoholics don't listen. You can tell her till the cows come home that she has to choose between you and the booze. I did that. And I didn't follow through. Guess what happened? He drew the conclusion I didn't mean what I said, and kept drinking.
When I left my ex, he was outraged that I would "just leave him without giving him a chance." Though I had told him for more than a decade that his drinking was breaking our marriage.
Please hang out here and chat with some folks. It's sometimes quiet on weekends, but people will come along and have good thoughts for you. I guess my advice would be don't panic. You don't have to solve it all today. Or even this week. You can think it through, figure out what you want to do. And then do it.