The celebrity couple just went public with their decision to separate earlier this year, and as multiple sources reveal to E! News, it's possible this split was in the making for quite a while.
"They completely grew apart," one insider shares. "This was a long time coming and they've been trying to sort everything out this past year."
Another source says it came down to Fergie and Josh's "completely different lifestyles" that ultimately drove them apart. "They have always had very separate lives and not a lot in common... There wasn't a lot of overlap in priorities," the source explains.
For example, our sources say the Transformers star is less concerned with living out his life in the public eye, while the pop star is concentrated heavily on her career.