Kaley Cuoco & Johnny Galeki split...

In what has proved to be THE BEST kept relationship secret in recent times, The Big Bang Theory cuties Kaley (Penny) and Johnny (Leonard) have in fact parted ways...even though it seems that no one knew they were actually together to begin with!

Kaley has told CBS Watch! magazine that they were dating for 2 years, part of which was when their characters were dating on the show and they broke up 6 months before their characters did but managed ok, obviously having to maintain an intimate onscreen relationship after splitting. 

"When you're dealing with two professionals who have been working since they were both 4—and who kept their lives extremely private—we didn't want anything other than that."

Ugh, they were such a cute couple on the show too, but huge ups for keeping it under wraps!

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