Kaley Cuoco celebrated her 31st birthday with boyfriend Karl Cook Wednesday with a night out on the town at celebrity hot spot Craig's in West Hollywood. Missing from the action were her friends. The Big Band Theory star celebrated this year's birthday a lot different then her 30th. Posting onto Instagram, "This time last year I was with 12 of my best gfs on the birthday trip of a lifetime in Mexico City. An adventure I will never forget!!!!! Love you girls!!!!?