Why can�t women be happy for other women?

I�ve figured it out. Well, atleast I think I did. I think I know why there is a constant case of cant-be-happy-for-each-other-itis between us ladies. I mean, come on, let�s be honest, shall we? We�re pretty good at hating on each other. Don�t look at me like that, you know it�s true. We are the queens of throwing shade, especially at another female�s perceived success� even more so at her