From romance rumors to anniversaries, here is a look back at the couple's relationship.
On June 30, 2018, Cuoco married Cook in San Diego, California.
On September 3, 2021, the two announced they are splitting up.
On September 3, 2021, Kaley Cuoco and Karl Cook announced their split after three years of marriage.
Following her divorce from tennis professional Ryan Sweeting, "The Big Bang Theory" and "The Flight Attendant" star Cuoco began dating Cook, a professional equestrian and the son of billionaire Scott Cook, and the duo tied the knot in June 2018.
Keep scrolling for a look back at Cuoco and Cook's relationship.
March 2016: Cuoco hinted at her new relationship
In March 2016, the "Big Bang Theory" star began hinting at her relationship with professional equestrian Cook by posting a series of sweet snaps to Instagram.
In an interview for the cover of Cosmopolitan's April issue, Cuoco spoke candidly about love and relationships.
"I cannot wait to be in love again," she told the magazine. "I don't feel like I am ready yet which is so different for me. I dive into everything."
Shortly after that interview, Cuoco appeared to confirm her new relationship on Instagram.
"That's what happy looks like," she captioned a photo posted on April 9, 2016.
Later that day, she posted another photo with Cook that was captioned, "When bae wins its a good night for this girl."
May 9, 2016: Cuoco and Sweeting's divorce was finalized
Although Cuoco and Sweeting had been separated since 2015, their divorce wasn't finalized until May 9, 2016. The actress and her tennis player husband called it quits after 21 months of marriage.
May 10, 2016: Cuoco said she was happier than ever following her divorce
"I'm excited to see what the future holds - but it happened, and now I have to say I'm happier than I've ever been," she explained.
When asked about her budding romance with Cook, Cuoco smiled and said, "He's special."
May 19, 2016: Cuoco and Cook packed on the PDA in a sweet Instagram photo
Although the couple had surely kissed in public long before this May 2016 photo appeared on Cuoco's feed, it was the first time they had been seen engaging in PDA on Instagram. If it wasn't clear before that the two were official, it was now.
July 31, 2016: Cuoco gushed about finally finding someone who shares her passions
Cuoco shared a photo of herself and Cook kissing while riding horses together. She captioned the photo, "Finding someone to share your truest passions with changes everything."
September 29, 2016: The couple made their red-carpet debut at the Longines Masters Los Angeles Gala
The couple stepped out in Long Beach, California, for what would be their first of many events together.
February 14, 2017: The couple celebrated their 1st anniversary
On Valentine's Day, Cuoco marked the couple's one-year anniversary of dating with a sweet Instagram photo of the two kissing while riding horses. "Every day since we've met has been better than Valentines Day," the caption read.
Meanwhile, Cook marked the occasion with a special selfie. "Not only is this Valentine's Day, but this is Kaley and my one year anniversary. So here is the very first kissy face picture I ever sent my love one year ago," he captioned the photo.
November 30, 2017: The couple announced their engagement
Cook proposed to Cuoco on her 32nd birthday.
In a video shared to Instagram, Cuoco can be seen crying and saying "yes" repeatedly after Cook jokes she didn't officially agree to his proposal.
Cook posted the same video with a caption that read, "After nearly two years I finally got up the courage to ask her to marry me. This is the best night of my life."
Earlier that day, he posted a photo of Cuoco with a joke engagement ring while the two were shopping at Target.
A few weeks later, the couple celebrated their engagement at Disneyland alongside Cuoco's sister and a group of friends.
June 30, 2018: Cuoco married Cook
Less than a year after Cook's proposal, the couple tied the knot in a San Diego, California, ceremony. Cuoco wore an intricate lace gown to the ceremony and changed into a lace jumpsuit for the reception.
On Instagram, she joked that the couple was now "Legally KCSQUARED."
"When your 'honeymoon' is shoulder surgery and your husband looks just as happy lol on the road to recovery," Cuoco captioned a hospital selfie she shared to Instagram.
During a September interview on CBS' "The Late Late Show With James Corden," Cuoco said she relied on Cook to do her hair during that time because she had limited mobility.
"He did a lot of top knots in my hair," she said.
December 14, 2018: The couple finally got to go on their honeymoon
After nearly six months of marriage, the couple finally went on their honeymoon trip to Switzerland.
June 30, 2019: Cuoco and Cook celebrated a year of marriage
One year after their San Diego wedding, the couple posted sweet tributes to each other on Instagram in honor of their anniversary.
Cuoco shared adorable wedding photos, and Cook opted for a series of hilarious videos and embarrassing photos of his wife from their time together.
August 2019: Cuoco said they are building their dream house
According to Entertainment Tonight, Cuoco told E! News in August of 2019 that she and Cook still were not living together, but were in the process of building their dream home.
"We have a very unconventional marriage, you know," she said. "We have different locations that we're at a lot. We're not together every single day."
April 6, 2020: Cuoco shared that she and Cook moved in together after almost 2 years of marriage
In an interview on ABC's "Jimmy Kimmel Live," Cuoco showed off her home, pets, and an extensive collection of mugs - all of which she now shares with her husband.
She said that the lockdown in response to COVID-19 urged the couple to take the next step and live together.
"This quarantine has actually forced us to move in together, it's been great for our relationship," Cuoco said. "And we like each other, we realized! Which is even better."
June 30, 2020: The couple posted about their 2-year anniversary
The couple celebrated their two-year wedding anniversary. Cuoco shared a photo from their wedding, and Cook posted a selfie.
Cook captioned his post, "By golly has it really been two since our wedding @kaleycuoco!! Feels like only a few moments! I can't wait for every moment year decade to come, I love you like crazy."
February 14, 2021: Cuoco posted a Valentine's Day tribute to her husband
In a heartfelt Instagram post, Cuoco shared a photo of the pair kissing while wearing masks with the caption, "Happy 5 years to the weirdest person I know! I don't remember a moment before you entered my life.. what a boring life that must have been! I love you."
"The Big Bang Theory" star Johnny Galecki, who played Cuoco's love interest Leonard on the show, replied to the caption by commenting, "Um." seemingly referring to the pair's former two-year relationship.
Cuoco quickly wrote back, "LOL," as the two have seemingly remained friends after their split.
September 3, 2021: Cuoco and Cook announced their split after 3 years of marriage
The two announced their split in September 2021. In an exclusive joint statement to People, they said that "there is no anger or animosity."
"Despite a deep love and respect for one another, we have realized that our current paths have taken us in opposite directions," they said in the statement.
They added that they made this decision out of "an immense amount of respect and consideration for one another" and that they "prefer to keep this aspect of our personal life private."
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