I regret getting married. I was young and stupid then, and there were plenty of warning signs that the marriage wasn't going to work, but I ignored them all. Spent seven years in misery until it was finally over.
I regret not taking better care of myself, but then I never expected to be around this long.
I regret losing touch with many of my old friends.
But mostly, I regret not living the life I should have lived.
The last time I experienced anything like that was during the total solar eclipse. So, in order for me to have it, as old and jaded as I am, it has to be pretty damn spectacular.