Well yeah, of course I regret EVERY bitcoin I have ever sold, but like Laszlo, you can't beat yourself up over what is gone.
We all hoped that this would happen, we knew it was possible, but back then it seemed far from certain.
Those 6 don't really bug me at all, the 100 that went to BFL? yeah, that one is harder to be philosophical about...
This is never happened to me, as I am too late into Bitcoin to have experienced such bad accidents.
But I think the best way to look at spent bitcoin is this one:
https://twitter.com/nic__carter/status/1130135656410300417Easier said than done.