Dear Prudence: Five years ago during the summer, when I was 19, my friend and I took a one-day trip to a nearby city. We left late at night after I finished my shift as a cashier. When I picked her up, her mother got so mad that we were leaving so late that she kicked her out of the house along with her dog.

While we were in city that day, we left the dog in the car. When we returned to the car in the evening, the dog was dead.

This was the worst mistake of my life. I think about it all the time, especially now, when it's so hot. I feel such pangs of regret and guilt that sometimes I feel like I am going to have a panic attack. I am so ashamed and wonder what we were thinking.

My mom made a point that I didn't leave the dog in the car with malicious intent. It was a mistake that I need to learn from and move on.

I know that I didn't do it on purpose, and I love animals. My mom suggested seeing a therapist if I can't stop thinking about it. I don't know what a therapist might say that I haven't thought of or considered already.

Do you have any advice on how to cope?

Prudence says: Since you keep going over the event, consider the precipitating one. Your friend's mother sent the family dog off late at night for a road trip with a couple of teenage girls. I hope that adult has had a chance during her own sleepless nights to consider the consequences of her temper.

You and your friend were a pair of young dopes whose thoughtlessness resulted in a dog's death. But five years later it is way past time for you to stop beating yourself up over a mistake.

Gene Weingarten won a Pulitzer Prize for his harrowing account in the Washington Post of parents who, distracted by daily events, made the deadly error of forgetting they left their baby in the back seat. His piece should help give you some perspective.

By now, you may have gotten so hooked on endlessly punishing yourself that you can't see a way to forgiveness. But the world is not made better by your being mired in guilt.

You love animals, so improve some of their lives and start volunteering at a shelter. I think reconnecting with dogs, seeing their tails wag at your arrival, can bring you the healing you deserve. If it doesn't, find a cognitive therapist who can help you address your obsessive thoughts.

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