When actor, Mel Gibson, lost his cool, he excoriated his wife with a tirade that she recorded. Mr. Gibson said in one of his outbursts that "I will give you one more chance." It is my opinion that Mr. Gibson was thinking that he had given up his previous marriage and long time wife for this relationship. I think Mr. Gibson was basing his decision to work things out with his new wife based sunk costs.
When I hear arguments one of the two parties are bringing up past events. There's nothing a party can do about what happened in the past, so this is a sunk cost. I think many arguments could be quickly resolved if the parties could only argue about relevant issues. However, when emotions are involved, it's easy to throw in everything that has ever happened into the fight.
On another irrelevant note, I think Mr. Gibson's privacy rights were violated. I think you'll see the audio tapes excluded as evidence. I don't doubt the veracity of the tapes, but how they were obtained. You will see Mr. Gibson sue Oksana Grigorieva for many torts.