Gossip Girl costars Chace Crawford and Ed Westwick are more than roommates - they're inseparable!

The preppy duo showed up at a show by Brit poppers, The Ting Tings.

"They were never more than a foot apart," a spy told The NY Daily News. 

"If one moved two feet to the left, so did the other.

"It was freaky."  

Westwick and Crawford also ignored the hordes of hotties trying to curry favor with the lads.

"They were only interested in each other," divulged the source.