Most girls choose to be socially accepted and split into two selves, one that is authentic and one that is culturally scripted. Girls learn to be nice rather than honest. Girls who have recently learned to bake cookies and swan-dive aren't ready to handle the offers for diet pills. Girls who are reading Pippi Longstocking aren't ready for the sexual harassment they'll encounter at school. Girls who love to practice the piano and visit their grandmothers aren't ready for the shunning by cliques.
Girls feel enormous pressure to be beautiful.
Appearance was important when I was in junior high, but it's even more important today. Girls who lived in smaller communities were judged more holistically - for their character, family background, behavior and talents. Now, when more girls live in cities full of strangers, they are judged exclusively by their appearance. Our culture sends messages that to grow up one must break free from parents, even loving parents. They are still young enough that they expect their parents to protect them and keep them happy.