We cannot change our history
When I was about ten years old, a friend accidentally fractured one of my teeth while I was riding a bike. She ran next to my bike and pulled on the handlebar, causing me to crash into the cement street. No going back in time to change that.

Some of us have had horrible childhoods, possibly even suffering terrible abuse. We cannot go back to change what happened. Or we might have been the cause of another person’s misery, e.g., the driver of a car in a tragic accident. Our history is ours to manage, no matter what. No matter how intense our longing might be for a different history, we cannot undo the past.