It’s no surprise to read that Robin Thicke’s performance with Miley Cyrus made the lines in his marriage to actress Paula Patton a little blurry. The two had reportedly hit a few bumps in their 20-year relationship before, but his appearance at the MTV Movie Awards with the starlet (who was born around the time Thicke and Patton started dating) really put their marriage to the test. At least that’s what a source told Us Weekly on Tuesday after the couple announced they would separate after eight years of marriage.

"The Miley Cyrus fiasco was a big test of their relationship," the insider said of their salacious "We Can't Stop" and "Blurred Lines" mashup. "He asked her to help him out as a friend and a wife, and defend him and the performance. He begged her to speak out for him and be there for him."

"She agreed to be the good wife after he begged and pleaded," the source explained. "Then he asked her to stick with him through awards season, and she agreed. She attended the Grammys with him as a favor."

And the “2 Guns” actress did just that: She defended her husband in public. "They rehearsed for three days. Robin told me in advance," Patton said on the "Today" show in September about Cyrus, then 20, twerking with Thicke, 36. "I thought it was great."

But before  Thicke’s phenomenal success with “Blurred Lines,” he told People magazine in 2011 that his marriage hadn’t always been easy. "It was hard when we became parents, because we had to balance our careers with this new person in our lives,” he said. Their son Julian was born in 2010.

"[Having a baby] changed everything," he added. "It was tough at first. She was stressed. I took time off. I lost my mojo. After a while, we hit our rhythm and we are more in love and supportive than ever."

Both Thicke and Patton are at the height of their careers, and their intense work schedules could have something to do with their failed relationship. "They're both at the top of their careers right now and they're never together. She's filming in Canada and he's on tour," the source said.

In their official statement to People magazine, the couple declared on Monday: "We will always love each other and be best friends, however, we have mutually decided to separate at this time.”

Apparently, the couple does intend on remaining close. "They do love each other,” and insider said. “They'll continue to be friends."

The "Cyrus fiasco" isn't the only problem Thicke and Patton reportedly had. After the scandalous performance, Thicke was accused of cheating on his wife various times, most recently at a night club in Paris in January right before the Grammy Awards.

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