Christine Costner’s recent divorce filing didn’t completely blindsideKevin Costner.
“But this is not what he wanted,” the source adds. “He knew that Christine was unhappy though.”
While Christine, 49, “wants them to spend family time at their Santa Barbara home,” the source continues, “during filming, Kevin is not around very much.”
“Hisabsence has been very hard for her,” the source says. “Christine doesn’t want him to throw himself into another project. He has been obsessed with filmingHorizonsince last year. She wasn’t happy about it.”
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Kevin Costner and Christine Baumgartner.Jamie McCarthy/Getty

Last week, a rep for theField of Dreamsactor confirmed that he and his wife of 18 years are breaking up after she filed for divorce. Christine listed their date of separation as April 11, and cited irreconcilable differences.
In astatement, Kevin’s rep said, “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.”
A source then told PEOPLE that divorce wasn’t Costner’s idea: “Itwas not anything that he wantedor sought, and if he could change the situation, he would.”
Kevin Costner and Christine Baumgartner.Rich Fury/VF22/Getty

Costner and Christinemarried in September 2004and theyshare three kids: sons Cayden, 16, and Hayes, 14, plus daughter Grace, 12. He is also dad tofour older children from previous relationships: Annie, Lily, Joe and Liam.
In November, theYellowstoneactor spoked with PEOPLE about raising a family with Christine, saying at the time, “The house is prettier because of her. Everything is warmer because of her. There’s these little things that she does — and I think it’s the power of love — but that she makes her home that way.”
Kevin added ofwhat he learned from fatherhood, “The world doesn’t revolve around you. It just doesn’t revolve around you. I work as a provider. I’m a father and I’m a husband, but it doesn’t revolve around me.”
TheOscarwinner waspreviously married to Cindy Silvafor 16 years before their divorce in 1994.
source: people.com