Mistakes committed by others should be forgiven and mistakes done by us should be forgotten.Keeping them in mind and thinking about the same mistake is of no use. But we should not do the same mistake. It is always better to reveal our mistakes to our near and dear so that we need not worry about the mistake again and again. We should practice forgetting these mistakes and concentrate on the other issues so that we will not commit mistakes again in another place.
Forgetting and moving on is not that easy because the deed is etched in our minds, revealing the wrong deed is not always possible, so, in a way, we are punished in this manner for the mistakes.
There's a nice quote about this, Guilty conscience never sleeps, for its sole purpose is to wake people up. The only happy note related to this is that at least the person has a conscience and it cannot accept the wrong even if others are not aware of it.
But, if that mistake involves others too and had hurt them in some manner we need to seek forgiveness of those people too. Only then, our guilty conscience could be relieved of the burden of guilt.
"It is hardest thing in the world to be good thinker without being a good self examiner"