OMG!!!! A BREAK-UP!!!!!!

It was fun while it lasted!

Gossip Girl's Chace Crawford has moved out of the NYC apartment he shares with costar Ed Westwick, a source tells Usmagazine.com exclusively.

The two have shared the apartment in the Chelsea neighborhood since they both first moved to the city after being cast in the hit CW series.

The source says Crawford -- who will star in the upcoming reboot of Footloose -- moved out on Monday and into a rented penthouse apartment in the luxe Dwell 95 building in NYC's Financial District.

The reason for Crawford's change of scenery?

Apparently, Westwick is a slob, and Crawford couldn't take the mess any longer, a source tells Us.

Source