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I also thought to mention that there is cheap software you can instal that will record keystrokes, incase you want to spy on your wife some more (and she has earned this spying with her dishonest behavior). If you face a divorce you might as well be well armed. Not only that, but you need to be aware of any other surprises your wife is planning against you.
Do you have a neutral friend or relative to talk to? You might seek an honest person who knows you both to find out just how big a clod you've been. Maybe you've been getting and ignoring warning signs for a decade or more. Maybe you wife is just a drama queen complainer who blames everyone else for her problems. You need to find out to make sound decisions. Some people (perhaps including you) are rather blind to what assholes they really are. In all this I'm assuming that these emails are an absolute admission of affairs, not interpretations on your part.