Whether in cave paintings or the latest uses of the Internet, human beings have always told their histories and truths through parable and fable. We are inveterate storytellers.
Ack! Parables. I hate parables.
You build on failure. You use it as a stepping stone. Close the door on the past. You don't try to forget the mistakes, but you don't dwell on it. You don't let it have any of your energy, or any of your time, or any of your space.