The couple later released the following statement: "After long and careful consideration on both our parts, we've decided to end our marriage. We entered our relationship with love and it's with love and kindness we leave it. While privacy isn't expected, it's certainly appreciated."
"They are being very civil about it," Us magazine's source says, noting that the spouses separated about two weeks ago.
Johansson, 26, began dating Reynolds, 34, in 2007. The stars announced their engagement in May 2008 and tied the knot that September in a remote wilderness retreat in Vancouver, B.C.
The source explains that "Iron Man 2" star Johansson initiated the split. At issue? "The big problem with their relationship is the distance," says the source. "They spent a lot of time apart when they are working...She's been unhappy for a while."
Johansson told Glamour last year that she's no expert on relationships. "I don't profess to know anything about marriage that anybody else doesn't know, or how to make it right," she told the mag.
"Green Lantern" star Reynolds, meanwhile, admitted in the October issue of GQ that things had "changed" since they got married. "I'm a little more guarded, I think," he said. "I'm a little bit more wary of having my relationship turned into a soap opera."
Still, he gushed at the time that marriage was the "best part" of his life.
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