::WHEN I REALIZED I WAS AN ADULT::
When I lived by myself, I realized I was an adult. All messes in the apartment? Mine. All bills sent there? Mine. All possessions? Mine. All secrets? Mine.
I had been with boyfriends and/or roommates since college, and there was nothing like ultimate responsibility to show me I was "grown up." More than getting married or paying for my own cellphone plan, even.
I will laugh at myself when I have a baby, though. I only THINK I'm an adult now.