Not a mutual decision. Kevin Costner is reeling after his wife, Christine Baumgartnerfiled for divorce earlier this month — but he still wants to work things out.

“Everyone thought Kevin and his wife were super happy so it’s all surprising,” a source exclusively tells Us Weekly. “He truly loves her and is trying to get her back. He’s been blindsided by this.”

Baumgartner, 49, filed for divorce from Costner, 68, on May 1, according to documents obtained by Us. The estranged couple tied the knot in 2004 and later welcomed three children: sons Cayden, 16, and Hayes, 14, and daughter Grace, 12. The Yellowstone star also shares daughters Annie, 38, and Lily, 36, and son Joe, 34, with ex-wife Cindy Silva and son Liam, 27, with ex-girlfriend Bridget Rooney.

The Oscar winner reacted to Baumgartner’s divorce filing via a statement from his rep. “It is with great sadness that circumstances beyond his control have transpired which have resulted in Mr. Costner having to participate in a dissolution of marriage action,” the May 2 statement read. “We ask that his, Christine’s, and their children’s privacy be respected as they navigate this difficult time.”

After news broke of the split, another insider exclusively told Us that Costner is “deeply saddened” by the divorce and is “still trying to save his marriage.” The insider continued: “Kevin loves his wife and children so this has been very hard on him. He is saying that this is his worst nightmare and he would do anything for his family.”

The Dances With Wolves director previously gave Baumgartner a shout-out for supporting him when he missed the Golden Globes in January due to flooding on the freeway near their home.

“Nobody’s sadder than us that we can’t be there at the Golden Globes,” he said in an Instagram video minutes before the show began. “Chris had a beautiful dress, I was looking forward to walking down the red carpet with her.”

Costner then shared that the handbag designer had bought him “some gold and yellow and black and silver balloons” to commemorate his nomination for his work in Yellowstone. The California native won the award for Best Actor — Television Series Drama later that evening.

Despite Baumgartner celebrating her estranged husband’s award win, a third source told Us on Tuesday, May 9, that Costner’s busy career contributed to their marital problems.

“Christine wasn’t happy with Yellowstone‘s schedule delays because it caused him to miss so much time with his family,” the insider explained, calling it “one of the reasons” for the divorce.

The source noted that the Field of Dreams actor was “on the fence about doing the show” — which films in Utah and Montana — from the beginning.

“He had to be convinced to do the project,” the insider shared. “There were months of discussions with Kevin and his family before he did it. He didn’t want do the show without their input.”

While Costner has not publicly addressed the split aside from his rep’s statement, he previously shared that fears of getting divorced again almost kept him from marrying Baumgartner.

“Finally, there came a moment where maybe this doesn’t go forward,” he recalled to Extra in July 2020. “Because I thought to myself, I could be divorced again, but what I couldn’t be is divorced again with children. That crushed me. I had to kind of face life and go, ‘Are you gonna miss life, are you gonna miss love because you’re afraid?’ And the answer finally came back, ‘I’m not gonna lose her because I’m gonna be afraid.’”

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Reporting by Andrea Simpson