Considering the 29-year-old's history with the 42-year-old, however, it's not ludicrous to believe they may be reconciling. Click through the gallery to see a timeline of their long and complicated relationship.
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Megan and Brian met in 2004 on the set of Hope & Faith. At the time, she was only 18-years-old and Brian had a child from his previous relationship with Vanessa Marcil.
"I didn’t know who he was from 90210, but I liked him right away. Everyone was around the monitor watching a scene, and Brian accidentally touched my leg. I remember literal electricity shooting through me and out me from every direction. It was like magic," she has said.
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After dating for two years, the couple got engaged in Nov. 2006.
He was 33 and she was 20 at the time.
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In 2008 Brian admitted that they hadn't made any wedding plans yet.
"No [we haven't made any wedding plans]. But we're solid… We've lived together for three years. We have tattoos of each other's names. We have more time away from each other right now than we'd like," he said.
"Right now, our biggest problem is rescuing pets from pet stores… we have a potbellied pig, we have dogs, two cats, two birds, a squirrel. And Megan wants a leopard. That'll never happen! That's a whole different world."
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The couple split in Feb. 2009.
"The reality is, she was 18 when I met her and she went through an enormous change in her life… just her career in general and going from being a girl who – when I met her, she was living in New York doing Hope & Faith and we'd go to restaurants and I was the person everybody would recognize and point and laugh at or whatever," Brian has said.
"And all of a sudden that turned around and she couldn't go anywhere and her name and her face were everywhere. So, she went through the natural period of, 'I'm not sure if I'm ready to be in such a settled relationship.'"
"I didn't want her to feel like she was stuck because she said she wanted to be in a relationship to begin with and we just never really went in different directions. We'd say, 'Oh, let's kind of take a break and see what's going on.'"
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In June 2009 the couple got back together.
Megan's rep confirmed that they were engaged again.
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The pair got married in Hawaii on June 24, 2010.
It was such a low-key ceremony that even Megan's mom wasn't invited!
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Megan and Brian welcomed their first child together – Noah Shannon Green – on Sept. 27, 2012.
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Less than two years later, Megan gave birth to her second child with Brian – Bodhi Ransom Green – on Feb. 12, 2014.
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In Aug. 2015 Megan filed for divorce.
"There is no prenup, so earnings during their 5-year marriage are community property and divided 50/50," a source said. "Megan will end up paying Brian spousal support, partly because of the disparity in income and partly because he's had medical problems."
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Brian and Megan were spotted together in early March, just six-months after their separation was announced.
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On April 11, Megan showed off a noticeable baby bump on the red carpet while posing with her Teenage Mutant Ninja Turtles co-star Will Arnett on the red carpet.