That's a thoughtful thing to do to pay it forward after biting someone's head off. I've had to go back in person and eat crow myself. I figure that I ruined their day the least that I could do is to apologize in person. The postmaster (yes, at our post office)thanked me for coming back. He said that you just don't find people who admit it and then apologize for doing it. He deserved better. I'm trying to show patience and understanding but it's hard. I'll say a prayer for you to find the peace to get through your troubles.