Allen Carr said in his book "Easy Way To Stop Smoking": if I would need to give the contents of the book just in 2 words I would say: stop be afraid. That's it. Have no fear and you can stop smoking. That is very deep thought, not easy to understand. That's why he wrote the whole book.
The more important thing is that this principle is applicable to other areas of our lives. In any conflict, stop feeling fear. Than you can win and overcome. Japanese samurais wake up every morning ready to die at that day. American Indians have an expression 'today is a good day to die'. That's why they are good and happy warriors. They have no stress, because they have no fear.
That is a secret for the happy life. We have stress and depression because we are afraid of something. Religious true believer knows (not just believes) the God. Thus, he is not afraid of anything happening in humans lives.
It is not a shame to lose. It is a shame to have fear.
Fear per se is much more harmful than the object of fear.
God helps us if we are true believers. We are true believers if we have no fear. God is the only one who should we afraid of.
I apply theory of fear to manage anger during stressful conflict. If I feel anger after the conflict, subconsciously it is anger towards myself because I was feeling fear during the conflict.