An attorney for Bullock did not immediately return calls to The Associated Press on Tuesday, but her publicist, Cheryl Maisel, confirmed the couple's split was complete.
James' publicist, Monique Huey-Jones, declined to comment Tuesday.
Their problems surfaced in March, just days after Bullock won the best-actress Oscar for her role in "The Blind Side." She had been on a career high — her romantic comedy, "The Proposal," was a box-office smash, then she swept Hollywood's awards season for her "Blind Side" performance.
The couple was a fixture at the glittery awards shows this year. She called James "sexy" as she accepted her Screen Actor's Guild award. Backstage, he held her purse as she spoke to reporters.
Bullock told James from the stage, her voice cracking with emotion: "There's no surprise that my work got better when I met you. Because I never knew what it felt like for someone to have my back." She did not thank her husband at the Academy Awards, instead dedicating her acceptance speech to mothers and parents everywhere.
Still, the couple walked hand-in-hand down Oscar's red carpet, celebrated together at the parties afterward and were photographed outside a Long Beach burger joint the next day.Ten days later, reports surfaced that James had been unfaithful while Bullock was away making her Oscar-winning film. He apologized to his wife and three children from previous relationships through a statement released by his publicist.
"It's because of my poor judgment that I deserve everything bad that is coming my way," he said. "This has caused my wife and kids pain and embarrassment beyond comprehension, and I am extremely saddened to have brought this on them."
Bullock canceled appearances to promote "The Blind Side" overseas, moved out of the home she shared with James and dropped out of sight. James went to rehab, but did not reveal why he needed treatment.
Bullock in April dropped a bombshell, announcing on the cover of People magazine that she was divorcing James and had adopted a baby boy who she intended to raise as a single mother.
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