Dad once said that breakups are like battles. They usually involve collateral damage. When former lovers fight, innocents get caught in the crossfire. The end of a long-term relationship is so destructive, it can impact friends, colleagues, people you’ve never even met. But that’s the nice thing about collateral damage. By definition, it’s completely incidental to the mission at hand. As long as the right people win, who cares if some random nobody gets hurt in the process? Acceptable losses, etc.