feel by your own

I learn since I was a child that no matter how problem or sadness you fell, just keep it by yourself.

But if you happy, you can share to some body else.

That time I do not understand the purpose of it.

But now I do. Because I had that experience.

It is because, if you share your sadness to somebody, there is no guarantee that they will understand you.
Sometimes, they are only said understand in lips, but in another time, they will fight back to you.

Somehow, people will understand if they are in same position like you do.