Dr Williams made it clear that the situation involving divorce being the most peaceful way was when one or both parties had NO INTENTION of keeping their vows.
That means that there is no reconciliation or coming to terms. There is no viewing the marriage as a promise to do the right thing.
I would say you are incorrect. If one or both parties have no desire to keep their vows, then divorce IS the right decision. You may not like it, but it is the right decision.