She is manipulating you. They are both cake eating big time getting the security from their marriages and the excitement from the affair.
Us vets know the signs we have read these stories hundreds of times. Most people are in denial when they get here because they just can't believe their spouse could ever do such a thing to them.
You need to try to take your focus of your W and place it on you and your kids. Dig down deep and decide if an affair is a deal breaker for you.
Be aware that most likely things have to get a lot worse before they can get better. Just prepare yourself for the long haul because I don't think things are going to change anytime soon.
