Trust yourself even in the most difficult times. I find great comfort in being able to trust myself and who I am, regardless of what may be happening in my environment. It does not matter who you are or where you come from. Your own individuality is beautiful and offers diversity in the world. Your unique story matters. Trust yourself and your abilities, do not let others define your limitations, because you are the only author to your story. You can stretch, bend, flex, and contort your mind toward whatever you feel is the correct path for you, and trust that your efforts are benefiting your own well being.
In a world full of conformity, it is certainly difficult to trust yourself and your abilities. It is difficult to resist the pull to uniformity, but doing so gives great satisfaction. Resisting the rest of the world's pressures to be one with external dullness is an act of great strength. You find yourself free from the evils of self doubt emitted by the external environment, and suddenly, you are floating in self appreciation. You are no longer bound by the hackneyed expectations of the outside world.
To feel jealousy for what others have is denying your own self greatness. Feeling jealousy takes your mind to a dark place; a place full of self destruction and evil. Remember that you are special, only if you resist the temptation to the dark side. Just trust yourself. Trust who you are, trust your innate abilities, trust your mind, and trust your heart. You provide the world with your own individuality, which is more than enough. Do not try to look for the greatness you think you lack but already possess in someone else. Just look deep enough within yourself.