That's an interesting observation, I didn't even notice. But I can tell you that men definitely think/feel this way too, I'm one of them! It's like a strange kind of bi-polar disorder where (like Tina Fey expressed) you're either riding the ego trip or trying to slide past the depression.

The worst part are the mistakes that inevitably occur during each 'phase'. When you're riding the ego trip, it's very easy to slip and make a fool of yourself or cause someone else feel stupid when they're not, while on the other end of the spectrum you make poor decisions because you feel like you're not good enough.