@Aaron Skidmore,
Stop acting like a child and grow up. Nothing you do is in "secret." You don't think your wife knows something is up? Your demeanor has changed, you're secretive and defensive. You're lying and hiding. All these things are tell-tail signs in a marriage that something just isn't right. You're on borrowed time.
If you're not happy, say so. Communicate your wants and needs. It may or may not include your wife. Or a mistress. You need "you" time, to figure out wtf you really do want.