Post all of your regrets, shames, insecurities, and past humiliations / mistakes.
I'll start.
My biggest regret is joining Epic Mafia, I've wasted so much of my damn time on this site and I'll never be able to get it back. If I could hop into a time machine before joining, I definitely would. So much time gone that could have been spent doing productive things like masturbating.
Now, your turn.