Contradictive!

"Grow up!" They said when they see me doing childish stuff. I only want to have fun once in a while
"Grown ups make their own decision!" They said when doubt my decision-making ability. I only ask for their opinion.
"What were you thinking?" They said when I make the wrong choice. I'm only human, I make mistakes.

Being human is complicated. People demand you to be an adult, make your own decision, go through your own life. But whenever you try to do so, the very same people scolded you, saying you're incapable of anything, calling you names that hurts. This is what I never come to understand. When you're being a grown up, they say you're still a kid. When you make childish mistakes, they say that you're an adult and should act like one.
What should I do then? Which kind of person should I be?