I can think of mistakes that I've made that I still get a bit of an internal "sting" from. I think for me, the mistakes last for just about as long as it takes for a success to come replace it. And it's rather topic specific. If it's a business mistake, it's not until that mistake is followed by a business success at which point I've completely forgiven myself for the mistake. So for me, the time cycle is never more than a few months or so. However, in my view, that's too long. I think, reviewing it, learning from it, grieving for about 24 to 48 hours if necessary and then getting back in the game with the same or heightened enthusiasm, but yet poised is what I'm gunning for as my habit for dealing with mistakes, failures and losses.
While it is an obvious question, it kind of resonated with me because of a couple of car crashes Ive had recently. Nothing major, just really really stupid ones and both my fault. Both as a result of not checking my surroundings clearly and carefully. I mean they were both different situations but still!