Trying to see it from a cultural perspective, how common is it that female character "dates up" in books, TV and movies (and in particular, those targeting a female audience)?

Thinking back at the show Grey's Anatomy, ABC's highest-rated drama show, got a female lead, and was among the top 10 shows in the US. A recent joke the character made was that all of them married their bosses. While fictional, culture impacts perception regarding behavior and in turns causes behavior.