How 'A Star Is Born' contributed to Bradley Cooper and Irina Shayk's split

Turns out, "A Star Is Born" did have a negative effect on Bradley Cooper's relationship with longtime girlfriend, Irina Shayk.

People reports that the intense filming process -- during which Cooper served as both director and star -- put too much space between the couple, and they ultimately weren't able to repair the damage.

"Bradley was emotionally absent during the long time filming 'A Star Is Born,'" a source explained. "They tried to save the relationship, but it had changed."

SEE ALSO: Bradley Cooper and Irina Shayk's relationship was 'hanging on by a thread'

Insiders revealed that "they couldn't break up when he was doing promotion for 'A Star Is Born'" because of the spotlight being shown on their relationship during that time.

Cooper and co-star Lady Gaga filmed the Oscar-winning film in 2017, and their intense chemistry both on screen and during the subsequent 2018-2019 awards season raised a lot of eyebrows, prompting speculation that their romance continued off camera.

Gaga put to rest any rumors of a romance between them following their intense performance of "Shallow" at the Oscars in February.

"People saw love, and guess what? That's what we wanted you to see," she said on "Jimmy Kimmel Live" after the Academy Awards.

Also making it difficult to know what was really going on was the simple fact that Cooper and Shayk maintained extreme privacy throughout their four-year romance.

"Since Bradley and Irina have always been very private about their relationship, few knew there was really for sure something going on," the People source explained.

SEE ALSO: Irina Shayk all smiles at the airport following Bradley Cooper split

Cooper did shed a bit of light on how the immersive filmmaking process affected their relationship, though, while accepting the BAFTA award for best original music. During his speech, the actor said, "Most of all I have to thank Irina, for putting up with me for all the music I was trying to make in our basement for a year. Thank you very much."

After awards season wound down, sources said that "Cooper slowed down to focus on his family" and "spent every day" with Shayk and their daughter, Lea De Seine, 2.

But, in the end, his efforts weren't enough, despite Shayk having "high hopes" for her future with the actor.

"Recently Irina decided enough is enough. She didn't feel she was getting the level of commitment she wanted and the endless fighting made their life unbearable," a source told ET. "They are very different people and once they realized it was the baby that was holding them together, it was time to call it quits."