You cannot see the past that did not happen any more than you can foresee the future.
If I was a young man, I might have bypassed the whole comedian-actor thing and just been a filmmaker. Then I'd probably have spent my whole life going, 'I wonder if I could have been a comedian.'
There is no remorse like a remorse of chess. It is a curse upon man. There is no happiness in chess.
I don't dwell in the past; I don't wallow in old events and emotions. I don't waste time on regret. No use going over and over the details of what already happened.
There's no future in spending our present worrying about our past.
It's a waste of time to think that if you colored a painting red what might have happened if you painted it black.
For better or worse, we live in possible worlds as much as actual ones. We are cursed by that characteristically human guilt and regret about what might have been in the past. But that may be the cost for our ability to hope and plan for what might be in the future.