LORELAI: You’re comparing me to my mother? … I’m Emily Gilmore? My, how the mighty have fallen.
A common expression meaning that those who were once powerful have now been reduced to a lowly status. The idiom comes from the King James version of the Bible, and is first found in Samuel 2 1:19, where it laments, The beauty of Israel is slain upon thy high places: how are the mighty fallen!
Lorelai always prided herself on being a “cool mom”, and now she discovers she’s actually a mother. A mother just like her own mother, Emily. Rory could hardly have said anything more hurtful to her. Bring on the tourniquet, her heart is bleeding.
The Annotated Gilmore Girls 