Kaley Cuoco and Johnny Galecki’s Relationship Through the Years: From Costar Couple to Friendly Exes

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Kaley Cuoco and Johnny Galecki's Relationship Through the Years: From Costar Couple to Friendly Exes

No hard feelings! Kaley Cuoco and Johnny Galecki have maintained a strong friendship since their 2009 split — and never let their personal lives get in the way of their professional bond. The actors worked together on the Big Bang Theory for 12 seasons from 2007 to 2019. When the series began, they sparked an offscreen romance but kept their relationship out of the spotlight before calling it quits. "We dated really early on for almost two years. When we did the pilot, I was crushing so hard on Galecki, but he had a girlfriend," Cuoco recalled during a November 2020 episode of Dax Shepard's "Armchair Expert" podcast. "We got together and just fell mad for each other for two years, but then we broke up. Luckily, Johnny and I came out of it so brilliantly and we're closer today than we ever were." Each of the actors moved on in the wake of their romance, with the 8 Simple Rules alum marrying Ryan Sweeting in 2013. Before she filed for divorce in October 2015, Cuoco said she felt "lucky" that her then-husband was such a fan of Galecki. "Johnny is actually one of my best friends. It's a situation that ended well. I understand sometimes it doesn't. It could have gone horrible," she said on Watch What Happens Live With Andy Cohen in September 2015. "He's one of my dearest friends and Ryan loves him. Johnny loves [Ryan]. I got lucky." [jwplayer m5NZfY1g-l3ahXupL Following her split from Sweeting, the Charmed alum and Galecki sparked speculation of a reunion more than once. Though Big Bang Theory fans would have loved to see the longtime costars rekindle their romance, Cuoco eventually tied the knot with Karl Cook in June 2018, with Galecki there to witness the magical moment. "Deepest congrats to the newlyweds. Love you both so much @normancook & @mrtankcook So moved by tonight. ❤️," the actor gushed via Instagram at the time, posing in between the married couple. Galecki, for his part, welcomed son Avery with Alaina Meyer in November 2019. The pair split one year later. Scroll down to relive Cuoco and Galecki's fun-filled relationship, from costar couple to friendly exes. [podcast_block]

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Offscreen Romance

The sitcom stars sparked a romance in the early days of Big Bang Theory, which premiered on CBS in 2007. At the time, the twosome kept their relationship private.

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Not Meant to Be

After two years of dating, the duo called it quits. It wasn't until after their split that the pair's Big Bang Theory characters, Penny and Leonard, got together on the show.

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Not 'Hiding' Anymore

One year after her breakup from Galecki, Cuoco opened up about why they were "so protective" of their relationship. "It was such a huge part of my life and no one knew about it," she said during an interview with CBS! Watch magazine in 2010. "It was a wonderful relationship but we never spoke a word about it and never went anywhere together. ... We knew how to keep it deep inside and never bring it on that set, ever."

Though she had fond memories of her time with Galecki, the actress admitted that the secretive romance "wasn't as fun as we wanted it to be" and that "hiding" their relationship "took a little bit of a toll" on them both.

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Big Friendship

Despite their breakup, the exes remained cordial as Big Bang Theory continued. "We're dear friends, still. Kaley's not just an ex, she's a part of my life. I just don't like to speak about it," Galecki told CBS! Watch magazine in 2013, noting that he didn't want his romantic history with Cuoco to "distract from the story" the sitcom was telling.

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No Drama

During a September 2015 interview on Watch What Happens Live With Andy Cohen, Cuoco revealed that there was zero tension between Galecki and then-husband Ryan Sweeting. One month later, she filed for divorce — and poked fun at those hoping for a reunion with her on-screen beau.

"So sorry to disappoint, but no home wreckers or secret flings going on here. Me and @sanctionedjohnnygalecki are just the best of buds," Cuoco wrote via Instagram at the time. "Leonard and Penny will just have to suffice!!! 💗💗❤️❤️."

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Platonic PDA

At the 2016 People's Choice Awards, Cuoco and her ex got cozy in the audience, but shut down reunion rumors once again. "Thank you for the @peopleschoice award!! Look how happy we are!! @bigbangtheory_cbs season9 #mydate #notdating 👊🏽💗😂😎," she captioned playful Instagram photos with Galecki at the time.

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Forever Friends

When the Flight Attendant actress wed Karl Cook in June 2018, Galecki celebrated happily by their side. "Couldn’t be happier for my fake wife @normancook and @mrtankcook whose words brought us all to tears last night," the actor wrote via Instagram after the ceremony. "So much love for you both."

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End of an Era

CBS announced in August 2018 that Big Bang Theory would be ending after its 12th season and Cuoco was dreading saying goodbye to the costars that had become like family. "I don't wanna leave, I don't wanna leave," she told Entertainment Tonight at the 2019 Golden Globes. "It's gonna be tough, it's gonna be a lot of emotions and I love our crew. ... Everyone is still madly in love with each other. We're all OK with the choice. We've just grown up together, so it's our adult decision."

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Doting Dad

In November 2019, Galecki welcomed son Avery with then-girlfriend Alaina Meyer. Four months later, Cuoco told Us that she "can't wait" to meet her best friend's little boy. "[Johnny] sends me pictures constantly. He's very proud," she said exclusively in March 2020. "It's really, really sweet."

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Too Close for Comfort?

Though they never let their past breakup get in the way of their work, Cuoco admitted that filming intimate scenes with her ex on Big Bang Theory posed its challenges. "When we broke up, obviously, it was a little sensitive for a minute," she said on a November 2020 episode of the "Armchair Expert" podcast, joking that she thought the writers created their characters' romantic story line "just to f–k with" them. "All of a sudden, these characters were all up on each other. ... Luckily, Johnny and I came out of it so brilliantly and we're closer today than we ever were."

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Still Inseparable

One year after welcoming their son together, Galecki and Meyer called it quits. Shortly after news of their split made headlines, the Roseanne alum gushed over Cuoco on her 35th birthday. "The happiest 74th birthday to my fake wife @kaleycuoco You know how much I adore you and respect you," he teased via Instagram in November 2020. "I'm so proud of all you are doing and so happy with your happiness. But most of all, our friendship and partnership over the years. XO, dear. Congratulations on 82 years of age." 

The Harley Quinn star replied: "THIS IS EVERYTHING! I LOVE U MOOKS! Even at my old age of 82!" 

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Lasting Bond

Cuoco shared that she didn't mind waiting for a potential Big Bang Theory reunion because she was still in contact with her former cast members, especially her onscreen husband.

"Johnny and I are very close," Cuoco told E! News in May 2021. "We talk multiple times a week. In fact, he literally — as this phone call started — he had just sent me a picture of his baby. He loves sending me baby pictures. I know it's really cute, we're really close."

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Birthday Tribute

"Happy belated 48th birthday to my / worldwide adored, Mooks. @kaleycuoco,” Galecki captioned an Instagram snap with the Flight Attendant star in December 2021.

Cuoco, for her part, replied to his sweet post: “😂😂😂😂😂😂😂.” She later reshared it onto her Instagram Story, captioning it, “He calls me Mooks” alongside a “Can’t Wait to Hug You” sticker.

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Forever Friends

While reflecting on their two-year romance for The Big Bang Theory: The Definitive, Inside Story, both Cuoco and Galecki gushed about their strong friendship. "I adore the friends that we are," the Roseanne alum said in an excerpt published by Vanity Fair in October 2022. "I think I might value my relationship with her more than any other previous relationship or relationship afterwards. ... We just have such a bond that I appreciate so much. And I think that’s part of our great friendship."

Cuoco, for her part, acknowledged that while there was "some hurt" after their breakup, her friendship with Galecki ultimately became stronger. "We really adored each other, and we were lucky because as our breakup was happening, there was no foul play, there was nothing bad about our relationship ... it just ended," she explained. "It didn’t take us that long to go back to what we were before we were dating and be friends. He was front row at both of my weddings, and we’ve been so supportive of each other ever since. We adore each other."