The Habit of being Happy

It sounds very easy and fun, like in Bobby McFerrin's song - don't worry, be happy.
When I was 14 years old, I had read the book of, nowadays, a classic inspirational writer Dale Carnegie "How to Stop Worrying and Start Living"
At that time, and very often now, it was hard to imagine for me not worrying because I was worrying about everything: my school, my appearance, my classmates, my teachers, and many other things, which any, relatively standard, teenager is worrying about. Therefore, for me it was an almost impossible task to digest and contemplate that book, but I have finished it and even memorized and tried to practice some parts of it.
Surprisingly, more than 17 years passed since, and almost everything in regards of worrying stayed the same, except the scene and probably some characters - classmates were substituted by colleagues, school by work; moreover, because my life has more activity, there are more things which "deserve" headache.
As a person with analytical mind, I am trying to find some logical and shortest way to solve this problem, before it reached its climax, after which normally follows an emotional collapse.
Practicing yoga and keeping a journal help me to focus on what important for me: my health and well-being of my family. However, sometimes, any person can be stupid enough to forget about these essential elements of one's life (yes, I want to be rude here and use word - stupid, because that how it is). This self-pity game happened to me last week again, I was on my way to C-train station, angry and unhappy about everything and everyone.
Then C-train arrived, I found a warm place to sit (do not forget about winter in Calgary), still contemplating my imaginary problems. Next to me was sitting a guy, tall, good-looking, strong jaw line, and skin which became rough from wind, from his clothing I was guessing that he was working at some construction site and was on his way home. He was chatting with his friend, smiling, in other words, he looked content. After some time, I have noticed that he doesn't have right hand, he was using his left hand dialing numbers on the phone, texting, and by the way he was doing it, was clear that he lost his arm just recently, a couple years ago. Watching him, I felt ashamed of my mood, my thoughts, which were minor compare to his or anyone's health related problems.
We dwell in the past or in the future, want some imaginary "toys", stuff, or promotions at work, then we get all above, and still being unhappy, we want more and more. Greed or constant desire of something imaginary, which, many generations were taught by Gordon Gekko, is good, occupied our minds like mantra, virus. Being pressured by media, which persuading us that we ARE already unhappy without some product: cereal, a shampoo, a car, a house (the list is limitless), we forget about the most important part of our life - the present, and everything, which surrounds us right now: our parents, friends, warm house, health.
There is nothing needed, to be honest, the rest of the list is just game, which we were forced to participate and toys, which we were told to acquire.
The answer sounds simple, but difficult to implement and practice every day, the state of being content and balanced should become a habit, which implanted into our minds. I have realized that reading the book "The power of habit. Why we do what we do in life and business" by Charles Duhigg, the power of habit, the habit loop, could be applied to almost everything: fitness, healthy eating, etc. and, also, I am pretty sure, to the state of happiness. It is not a part of personality, it is a habit which should be trained, nurtured every day.
I was lucky, my mom have thought me some elements of life-enjoyment. However, being many thousand miles from her, here in Canada, doesn't help me, and I forget, sometimes, the simplicity and importance of developing this habit. My mom could have been a professional motivational speaker - she knows a lot about Habit of being Happy (let's name it this way). She was born in a very poor family in the Southern part of Ural Mountains, Russia. When she was one year old, she had lost her right eye. Imagine being a teenage girl in 60s with one eye. My mom had been spending all her teenage years at the library, hiding, from such immature and very often cruel world, behind book shelves. What I admire in her the most that she did not give up, she studied very hard, entered the University to become a veterinarian. There, she joined various student groups, where she had met my dad, a bright and handsome guy. And here I am. All my childhood I do not remember any whining, complaining about life difficulties (trust me, life before, during, and after Soviet Union collapse was tough), there always was hope and enjoyment of life each moment.
My mom still knows how to cheer me up, when I call her, she knows a lot about Habit of being Happy. And, I assume, we all have a choice to obtain this knowledge and keep it in our hearts.