On a more important note (as the busting up of this affair is fairly easy), what do you suppose made her vulnerable to this guy's approaches to begin with, Committed? Think hard: you say you had a "perfect marriage," but were there some ongoing relationship complaints that you failed to address?
What would you say is your wife's primary love language (re: Smalley's "Five Languages of Love" -- acts of service, gift giving, quality time, words of affirmation, physical touch)?
I'm not asking you to take responsibility for your wife's affair -- that is hers alone. She should have come to you, no matter WHAT her complaint, and tried to work on her marriage instead of taking such a destructive and selfish path. But there must have been SOMETHING that you can work on?