Everybody wants what they don't have?

For example I know a girl who has pretty dark brown eyes and often wears bright blue contact lenses. They look fake and I wonder why she does that...obviously she wishes she had light eyes sometimes. However I have light blue green eyes and have always wanted dark eyes. I have very pale skin and am very short....have always wanted to be taller, curvier, and tan. Have you experienced this feeling of wanting THE OPPOSITE of what you have? How do you get over it? Just curious no dumb azz comments plz.