From the Ethicist feature in NYTimes Magazine: Should I Tell My Friend’s Husband That She’s Having an Affair?:
... [If] your assessment is accurate, you are in a deeply compromised moral situation — one in which the cure is worse than the condition. As is so often the case, there’s no way out from under the net. It’s a distressing bind. Moral narcissism is about being more concerned with the cleanliness of your hands than with how your conduct shapes the lives around you. Your sensitivity to this pitfall is commendable. So is the fact that what you’re doing — though the least bad option — bothers you. Life is messy, and the best outcome often has something deplorable about it. I suppose it’s all in the title of the great Bronzino painting that one of Iris Murdoch’s characters found so captivating: ‘‘Venus, Cupid, Folly and Time.’’ If the day comes when Peter asks you why you helped Jane conceal her betrayal, you can tell him the truth. He won’t forgive. But he just may understand.