I read a book "the courage to be disliked" that changed my life. Let me share with you what I learnt.
Happiness is not an ambiguous feeling. After hearing this, you can be happy immediately forever, or else, you would never be happy.
Happiness can be directly translated to a sense of contribution. This sense of contribution is derived from your sense of self worth. The problem is, many peoples' sense of self worth is on the level of acts instead of the level of being. To give you an example, someone who gives his all when playing badminton, often angry and complaining when things arent going their way, might find his self-worth by being a better badminton player than his peers, and a feeling of other people acknowledging that he is the best.
What I am about to say is going to sound counter-intuitive to people who complain about things: people actually act in accordance to what they believe gives them self worth, which in other words means, they act in accordance to what gives them happiness. In the case of the angry badminton player, his complaining explains why he isn't performing up to the standard of being better than everyone else. Hence justifying why he still has self worth. That he is actually better than all his peers if not for these problems he is complaining about. People act in accordance to what they subconsciously believe, gives them self worth and hence happiness. In the case of a sole breadwinning father, he may derive self worth from a sense of importance in his family. He wants his wife and children to be grateful for his provision, and upset when he doesn't get the respect he deserves. It is not unusual to see such a father when laid off his job, feel worthless and unhappy. Even when he continues to earn a big paycheck, such a father continues to act in accordance to his sense of self worth, such as by nitpicking on what he considers his children's/ wife's flaws, subconsciously trying to show that his family cannot function without him. While he believes he has his family's best interest at heart, if his self-worth is at stake, he would subconsciously subotage his family, making them feel inept, in order to maintain a sense of importance.
Everyone without exception, acts in accordance to a goal they believe would lead them to a feeling of self worth, and hence a feeling of contribution, which is happiness.
Another common example in the family could be the housewife who derives her sense of self worth from being a protector of her children. Despite her occassional grumbling of how her child is messy or unpunctual, she derives her self worth from protecting the child from drowning under his or her mistakes, such as by preventing him or her from being late for school. When her husband or other people say anything negative about her child, she will subconsciously prevent the child from hearing any of such things that may hurt his or her self esteem, even if to the detriment of the child.
When a person derives his or her self worth from an act, happiness is fleeting, a goal that needs chasing. In order to find eternal happiness, a person needs to develop a sense of self worth from the level of being, to feel strongly one's self worth from their very existance. Such a person, is happy just from being alive, and nothing can take the happiness from that man. All unhappy people are unhappy because they lack courage to shift their sense of self worth to being. They would generate all sorts of excuses as a means to avoid having the courage to be happy. As such, happiness is a choice of courage that can be taken by all people, the priviledged and the unpriviledged, whatever the circumstances.
So how to choose happiness? To truly feel self worth from a level of being, you must first learn to see all people as equals. It is important then to see even your students, children or employees as fellow brothers and sisters, who you have the opportunity to share the journey with. A person can only choose to have all his interpersonal relationships as equals. A failure to see even one person as an equal would make one person's interpersonal relationships be totally that of a hierarchical relationship. This is critical because hierarchical relationships of all levels means that you unwittingly develop a superiority or inferiority complex towards every interpersonal relationship. You either see yourself as the one ought to be listened to, the one whose advice the other person should take, or be too afraid to speak freely and feel a sense of distance from someone you deem is above you. Only where you can see everyone as equals, can you feel self worth from an existential basis. Because when building hierarchical relationships, you are, in fact, deeming one person's worth greater or lower than another. Hence your worth likewise has to be greater or lower depending on acts. A sense of self worth from the basis of being has no hierarchy. All problems of unhappiness stem from hierarchical interpersonal relationships.