From Abaddon's Gate by James S.A. Corey
"This isn't about good guys and bad guys," Anna said. "Yes, we've picked sides now, because some of the actions they are about to take will have serious consequences for us, and we're going to try to stop them. But what you're doing is demonizing them, making them the enemy. The problem with that is that is that once we've stopped them and they can't hurt us anymore, they're still demons. Still the enemy."
"Believe me," Tilly said, "when I get out of here, it will be my mission in life to burn Cortez to the ground for this."
"What do you mean, why?"
"He won't be on a ship trying to destroy the Ring anymore. He won't be supporting Ashford anymore. All of the circumstances that made him your enemy will be gone. What's the value in the clinging to the hate?"