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Lack of self-confidence is, as usual, a lack of consistency over hard work. Educate your parents to smart work the rest of your life, free.
That's a great tip. Envy is a sign that you are not focused on your life. In the long run, people with average talent who consistently get things done tend to outcompete talented people with a lot of potential who never deliver because of their mental instability.
The more insecure you are, the more you seek control over other people, the more confident you are, the less you worry about other people being able to leave you anytime because you know you are what, because you know you will eventually be surrounded by the people you deserve.