this is what I read at the moment.
I love Matt Haig's fascinating idea: to be able to test different lives that would have been the result of not choosing the one option you actually took.
Consequences of choices that one made - or didn't take.
Makes me think a lot ... what would have been if...
On the other hand - to stay content and sane - my motto is:
"Yesterday is over and the door to tomorrow is still closed. Today is all you (really) have."