When my wife was having her affair, I absolutely saw her as my adversary. The AFFAIR was my adversary, and my wife -- at least in her current wayward state -- was also an enemy of our marriage and our intact family.
It was damned hard -- and horribly sad -- to come to that realization, but I honestly don't see how you can effectively DB without that mindset. To my way of thinking, you cannot negotiate the peace without first pacifying your enemy.