Is love dead? Fergie and Josh Duhamel, who first met on the set of NBC's "Las Vegas" in 2004, have decided to call it quits after more than eight years of marriage.

Fergie and Duhamel made the announcement through a joint statement released to PEOPLE. It was revealed that the couple decided to go separate ways seven months ago, but kept it private until now.

"With absolute love and respect we decided to separate as a couple earlier this year," the estranged couple said in a joint statement. "To give our family the best opportunity to adjust, we wanted to keep this a private matter before sharing it with the public. We are and will always be united in our support of each other and our family."

Now, a source close to Fergie and Duhamel has started spilling the beans on what actually went wrong. Allegedly, their differences have contributed to the end of their eight-year marriage; the singer-songwriter is naturally outgoing, while the 44-year-old actor is more quiet and reserved.

"Josh is low-key and laid back, [while] Fergie is more high maintenance and very focused on her career," the source said. "He definitely wants more kids and has always wanted to be a family man."

On top of that, Fergie and Duhamel are unable to spend much time together due to their respective busy schedules. For the past months, the Black Eyed Peas member has been busy working on her comeback album "Double Dutchess," which is set to be released on Sept. 22.

The former fashion model, on the other hand, recently wrapped up filming on the upcoming comedy-drama film, "Simon vs. the Homo Sapiens Agenda." In it, he plays Jack Spier, the father of a 17-year-old closeted gay teenager (Nick Robinson).

Despite the split, Fergie and Duhamel maintained an amicable relationship for the sake of their four-year-old son, Axl Jack.