I think what Cobra is trying to get to is... it takes two people to make a marriage and it takes to people to break it. Your H deciding to have the affair was his sole responsibility. But up until that moment, the R deteriorating to a point that he was vulnerable enough to make that decision, you did play a part in.
And if you thought everything was great and strong and you were being all you could be... (even strong marriages are vulnerable)... there IS a part you played in it. For it takes two people to make a marriage, and two people to break it.
I think he is wondering what you think YOUR part in that was...
