Kaley Cuoco Reveals the Sweet Way Her Big Bang Theory Costars Protected Her amid Ryan Sweeting Divorce

Kaley Cuoco is looking back on the day she announced her divorce from Ryan Sweeting.

In Jessica Radloff's new oral history book The Big Bang Theory: The Definitive, Inside Story of the Epic Hit Series, the actress, 36, opened up about how the set of the CBS sitcom was "a really wonderful escape" amid her personal turmoil.

On the day her divorce was made public in September 2015, Cuoco recalled Entertainment Tonight visiting the set and watching her film a scene with costars Johnny GaleckiJim Parsons, Kunal Nayyar and Simon Helberg for an episode in the show's nine season, titled "The 2003 Approximation."

"I was in a scene in the comic book store, wearing a purple sweater, and sitting on the couch between Jim and Johnny, while Simon and Kunal were singing this ridiculous song in their little band. And I am hysterically laughing. Genuinely. And they used it," she shared. "And that was the scene we were shooting when ET was watching us, and I remember sitting there, thinking, 'My divorce is about to be announced right now.'"

"The Comet Polarization" - Pictured: Howard Wolowitz (Simon Helberg), Leonard Hofstadter (Johnny Galecki), Rajesh Koothrappali (Kunal Nayyar), Penny (Kaley Cuoco), Sheldon Cooper (Jim Parsons) and Amy Farrah Fowler (Mayim Bialik). Sheldon's comic book store experience changes when writer Neil Gaiman puts Stuart's store on the map. Also, Koothrappali takes credit for Penny's astronomical discovery and friendships are threatened, on THE BIG BANG THEORY, Thursday, April 19 (8:00-8:31 PM, ET/PT), on the CBS Television Network. Photo: Jordin Althaus/Warner Bros. Entertainment Inc. © 2018 WBEI. All rights reserved.
"The Comet Polarization" - Pictured: Howard Wolowitz (Simon Helberg), Leonard Hofstadter (Johnny Galecki), Rajesh Koothrappali (Kunal Nayyar), Penny (Kaley Cuoco), Sheldon Cooper (Jim Parsons) and Amy Farrah Fowler (Mayim Bialik). Sheldon's comic book store experience changes when writer Neil Gaiman puts Stuart's store on the map. Also, Koothrappali takes credit for Penny's astronomical discovery and friendships are threatened, on THE BIG BANG THEORY, Thursday, April 19 (8:00-8:31 PM, ET/PT), on the CBS Television Network. Photo: Jordin Althaus/Warner Bros. Entertainment Inc. © 2018 WBEI. All rights reserved.

Jordin Althaus/Warner Bros.

RELATED: Kaley Cuoco Recalls Getting Married to Ex-Husband Ryan Sweeting After 'Like Six Seconds'

The Flight Attendant star added the performance provided her with a much-needed relief from her personal life.

"Simon and Kunal had me laughing so hard that tears were coming down my face as they were performing this song, and I just got to sit there and watch them as Penny, but it was also me," she explained. "And it just took me totally out of what was going on in my personal life. And everyone [in the cast] knew what was going on with me and they were very protective."

She continued, "I just remember the drama going on behind the scenes, but shooting that scene was a really wonderful escape."

Kaley Cuoco
Kaley Cuoco

Araya Doheny/Getty Kaley Cuoco

RELATED: Kaley Cuoco Reflects on Ryan Sweeting Divorce: He 'Was Not the Person I Originally Met'

Cuoco and Sweeting got engaged in September 2013 after three months of dating. The couple tied the knot in December of that year. The former couple then announced that they were splitting up just 21 months later.

According to court documents obtained by PEOPLE at the time, Cuoco filed for divorce, citing irreconcilable differences.

RELATED VIDEO: Kaley Cuoco Reflects on Ryan Sweeting Divorce: He 'Was Not the Person I Originally Met'

Cuoco — who is now expecting a baby girl with boyfriend Tom Pelphreytold Cosmopolitan in 2018 that Sweeting "completely changed" throughout the course of their relationship and she didn't know whether she'd ever feel ready to walk down the aisle with somebody else again.

"I honestly thought I wouldn't get married again. My ex ruined that word for me," Cuoco said at the time. "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."

Kaley Cuoco and Ryan Sweeting
Kaley Cuoco and Ryan Sweeting

Michael Tran/FilmMagic Kaley Cuoco and Ryan Sweeting

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The Big Bang Theory: The Definitive, Inside Story of the Epic Hit Series is available now wherever books are sold.