On Friday, the Flight Attendant star, 35, and Cook, 30, announced in a joint statement that they would be going in “opposite directions.”
A source told People the couple appeared to be happy in their relationship when they last saw them, which was at the beginning of summer in the US, and that there had been no indication they were going to break up.
“Kaley seemed very happy with Karl,” the insider told the publication. “They were affectionate and seemed great.
“The split seems very sudden. It’s pretty shocking.”
The pair had appeared to be displaying signs of being a happy couple, with Cuoco recently sharing a sweet black and white throwback photo to mark their third wedding anniversary.
“I love you oh so much you have no idea,” she captioned part of her post from June.
“Despite a deep love and respect for one another, we have realised that our current paths have taken us in opposite directions,” they said.
“We have both shared so much of our journey publicly so while we would prefer to keep this aspect of our personal life private, we wanted to be forthcoming in our truth together. There is no anger or animosity, quite the contrary.
“We have made this decision together through an immense amount of respect and consideration for one another and request that you do the same in understanding that we will not be sharing any additional details or commenting further.”
Cuoco began dating Cook, an equestrian, in 2016. The pair got engaged on her birthday in November the following year.
The actress was previously married to tennis star Ryan Sweeting in 2013 for just 21 months.
“I honestly thought I wouldn’t get married again,” she told Cosmopolitan in 2018. “My ex ruined that word for me. I married someone the first time who completely changed. The person I ended up with was not the person I originally met. And that wasn’t my fault — that was his.
“I knew how much I had to give and how much I wanted to receive. I knew I just had to be patient … I had to go through a lot of things, but it brought me to Karl.”
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