Someone said to me about the key to be happy. Those are patience, gratitude, and sincerity. To be honest, my mother and my mother in law often advise me like that too. 

Don't get me wrong, these three attitudes don't mean passive, but the opposite. For example, being patient doesn't mean we do nothing.

In life, we don't always meet the things we like. In life, we don't always get what we want.  

Whatever challenge, face it!