The couple, who have two sons, Noah, two, and Bodhi, 18 months, together, are currently taking "some time apart" from their marriage, but haven't completely ruled out a reconciliation and friends believe "anything could happen in the future."
A source close to the pair told PEOPLE.com: "They will always love each other very much and are devoted to their kids. Anything could happen in the future, but for now they've decided it's best to take some time apart."
The pair tied the knot in Hawaii in 2010, but have been together for 11 years.
The 'Teenage Mutant Ninja Turtles' star, 29, and the 'Anger Management' actor, 40, are said to have quietly separated six months ago due to arguments over Megan's hectic career.
Another insider previously said: "Megan has separated from Brian. They decided on it six months ago.
"They fight about her career. She was obsessed with getting roles. She has gone off and done her own thing recently."
The brunette beauty confessed last year that she and Brian rarely got to spend any time alone together.
She said: "Brian doesn't get any intimacy whatsoever."
But she also insisted she worked less than 20 days a year in order to be with their family.
She said: "I have to make one movie a year because I have to invest in their future and I have to be able to pay their way through college and be able to provide for them. I'm looking for movies that will shoot in Los Angeles, for projects where I'm part of an ensemble so I can shoot in and out in 10-20 days. It's all about trying to spend as little time away from my kids as possible."