Most people have not trained their brain. The result is that their brain just thinks about whatever it wants, whenever it wants, for as long as it wants.
The result is that many people are stuck in whatever mood they happen to be in, sometimes sad or depressed, and often for years at a time… and they wonder why they are not happy.
They key is to take charge of your brain. You decide what you are going to think about. You decide what emotions you are going to feel. Take charge! Stop believing that thoughts and emotions are things that just happen to you and you have to honor them and feel them even deeper, or to give them the space they need! Honoring these thoughts and emotions just locks you in to those thoughts and emotions long term.
The human brain loves drama. The default position is to look for things to be sad or unhappy about, or to complain about. We humans complain about everything. Complaining has replaced conversation for many people.
This is no way to be happy.
Gratitude is the way to be happy. Brain scans have shown conclusively that thinking Gratitude thoughts will cause your brain to change its chemical balance and actually rewire to happiness.