There is an inherent property of reality. Past must be accepted. It's immutable. Doesn't matter how it went. How good or bad it was. There is only one thing you can do with it since it's carved in stone, or a mountain. Embrace it. Consent to it. It's neither defining nor definitive. As long as you have the present, there is no past. Each new second is as new as it can be. No grudge no mourning.