The Big Bang Theory star Johnny Galecki opened up about his one-time relationship with current co-star Kaley Cuoco.
After dating Cuoco, 27, for two years, the 38-year-old actor told CBS Watch! Magazine, "We're dear friends, still. Kaley's not just an ex, she's a part of my life."
The actor also revealed why the couple kept the relationship secret when they were together, saying they didn't want their personal lives to affect the relationship their characters have on the show.
"I just don't like to speak about it, and not because I'm trying to be enigmatic," he said. "I just worry that it will conflict with people's acceptance of Leonard and Penny. I get the curiosity, but I just don't want to distract from the story."
Cuoco talked about her relationship with Galecki in 2010. She told the magazine the time spent dating her co-star "was such a huge part of my life and no one knew about it."
"This is the first time I've ever talked about it, ever," she said at the time. "It was a wonderful relationship, but we never spoke a word about it and we never went anywhere together."
Cuoco is now engaged to tennis professional Ryan Sweeting, while Galecki is dating former Pan Am star Kelli Gardner.
The Big Bang Theory, now in its seventh season, airs Thursdays at 8 p.m. on CBS.