Bang! Kaley Cuoco's engagement to addiction special Josh "Lazie" Resnik is off, a source confirms to Us Weekly.

ETOnline first reported that the Big Bang Theory actress, 26, announced the news Thursday night at an L.A. event honoring Chuck Lorre, the TV honcho behind her CBS smash as well as Two and a Half Men, Dharma and Greg and other sitcoms.

Asked whether her costar Kunal Nayyar's recent wedding gave her any wedding-planning ideas, Cuoco quipped with a giggle, "I'm not engaged anymore, so no…But in general, yes. For my future wedding, yes!"

She and Resnik announced their engagement last October. The star's last known relationship was with Big Bang costar Johnny Galecki; the pair kept their two-year relationship completely under wraps.

"No one knew about it," Cuoco told CBS Watch Magazine of her undercover romance with Galecki, 36. "It was a wonderful relationship, but we never spoke a word about it and never went anywhere together."