Why is our immediate reaction to being hurt to turn around and hurt someone else? Is it a knee-jerk reaction?
Is it instinct, or is it just a habit? Is it really so hard a decision to NOT lash out immediately after? Instead of causing more pain and anguish, why not just brush it off and keep going?
Pain begets rules. Rules beget action(s). Action(s) create unforeseen scenarios. And unforeseen scenarios create more chances to hurt again.
So skip the rules. Pain should be nothing but a training tool; learn and be wiser to avoid the painful circumstance, instead of trying to set rules to avoid it. Wisdom is not as easily broken as rules are.