Like Kat said, it's this need to keep up an appearance of being happy. We don't want others to know we don't have it all together all the time.

My dad absolutely hated it when I cried. He would yell and scream at me to stop. Which would only prompt me to cry more because I didn't know how to stop crying.

Now that I think about it, he was probably projecting his own insecurity of feeling not able to cry. Always needing to be "super-dad" to the rescue.

He was frustrated I had no "self-control." Or that I couldn't handle one little criticism because of the way my parents raised me to be a perfectionist.

People see crying as weakness. Not as the strength to admit that you don't know the answer sometimes.