Stress

No matter how easygoing you are, life can get stressful. And when stress takes over, even for those who appear to have the calmest center, it can be a chore to find your Zen again.
The emotional demand of stress can build up over time, but if you learn to silence the outside world, if you find an unshakable peace, you’ll find a way to return to your happy place, no matter what.
Who we are is determined not by the times in our life when it's happy and good and all nice things are happening, it is truly established by the times in which we are stressed and have a lot of things going on, or everything seems chaotic. In other words, who we are under stress, is closer to our real self.