“The primary cause of unhappiness is never the situation but thoughts about it. Be aware of the thoughts you are thinking. Separate them from the situation, which is always neutral. It is as it is.”
This is a very deep quote. I really like it. Unhappiness is caused by your thoughts about everything, it isn’t from the actual situation itself. If you master to change your thoughts you will be able change your outlook and how you view the world. Never let your emotions or thoughts ruin a good day.