Los Angeles - Hollywood couple Ben Affleck and Jennifer Garner were in therapy for two years and had a trial separation for 10 months, before they decided to divorce, said reports.
People magazine and E! website said the two had fought to save their 10-year marriage before they announced their split on Tuesday, a day after their wedding anniversary.
A source told People: "He's devastated. Nobody intends to go down this path. They both battled and he really battled to try and save the marriage but ultimately it was the best thing for the kids and for him and Jen."
TMZ website, quoting unnamed sources, said Garner, 43, had felt neglected as a wife, after the career of Oscar winner Affleck, 42, exploded and he spent much of the past few years away making movies.
The site said: "Ben felt he was a good husband, who was juggling his career and family, but it wasn't enough for her."
Rumours of marital woes had been rife after moving vans were seen at the couple's Southern California home.
People said the two were renovating their house and are living together for their three children for the time being.
E! said Affleck checked in and out of hotels during the trial separation and will now reside on the couple's property but in a different building.
A source told E!: "They grew apart. They were great parents together but they were not always on the same page."
The couple starred together in the 2003 superhero film Daredevil and married in 2005. They have two girls and a boy, all under the age of 10.