I’m not sure to whom this quote is attributed, but it really says a lot about human relations. There are certainly battles worth fighting, but many are not. Sometimes it’s ok to say you’re sorry simply because love or respect the other person and continuing to fight serves no long term purpose. 

Closely related to this quote would be one I saw on a car the other day, “wag more, bark less”. Calm down and try to see things through someone else’s eyes, it might just change how you perceive things.