Every time you snap back, you let someone else pick your mood for the next hour.

The reply takes a second and the aftermath runs much longer, through the replaying, the justifying and the low hum of irritation that follows you around. Whoever provoked it has usually moved on well before you have. The real cost is not the exchange, it is the hour afterwards.

Before responding to something that stings, ask what you want the next hour to feel like. If the answer is not this, leave it unanswered and go to the next thing on your list. You can always come back to it, and you will rarely want to.