(Yahoo!) - Better late than never!

Johnny Galecki is finally opening up about his secret romanceof two years with "Big Bang Theory" co-star Kaley Cuoco.

"We're dear friends, still. Kaley's not just an ex, she's a part of my life," the 38-year-old actor tells CBS Watch! magazine. Cuoco first spilled the beans about their romance to the same outlet three years ago. So why has it taken Johnny so long to discuss their past relationship?

"I just don't like to speak about it, and not because I'm trying to be enigmatic, I just worry that it will conflict with people's acceptance of Leonard and Penny," he explains, referring to their TV characters from the hit show.

"I get the curiosity," he adds, "but I don't want to distract from the story."

Kaley first discussed their undercover relationship in September 2010.

"We dated for almost two years. It was such a huge part of my life and no one knew about it," Cuoco told CBS Watch!. "This is the first time I've ever talked about it, ever. It was a wonderful relationship, but we never spoke a word about it and never went anywhere together."

Being so private eventually took a toll on the dynamic duo.

"We knew we weren't destined to be together. We accepted it and said, 'Look, if we ever break up, we will be professional,'" she elaborated. "I'm so lucky it was a mutual ending and that we don't hate each other. We've seen that happen on other shows."

Both Johnny and Kaley have clearly moved on. The actress is now engaged to tennis pro Ryan Sweeting, and there are no hard (or awkward!) feelings between the exes.

After Cuoco's sudden engagement in September, Galecki told E! News he's "very, very happy for her."

"She's very happy, which makes me terribly happy," he added.

Glad to know there is no tension on set of TV's number 1 comedy!

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