An addition to teaching 1:
I had been taught that acceptance or rejection by one’s parents is the major determinant in how you feel about yourself. There is another source of acceptance or rejection, I believe. It is one’s social environment. If you are the alien, the one who doesn’t fit in to the prevailing religious or political ideology and you are made to feel like the outsider, you may work hard to please others in order to be accepted, even though you were accepted by your parents.