An anonymous source (aka, probably someone on the couple's payroll) told Us Weekly, "They realized they are in different places in their lives. They grew apart."

Kate recently premiered her new movie with Zach Braff -- Wish I Was Here -- at Sundance without Bellamy, and she's been spotted with her ring, which always makes people suspicious... like they never felt like being bling free or forgot to put on their jewelry!

The couple have been engaged for three years and have a 2-year-old son together, Bing. For him, I hope there's nothing to the rumors.

Photos: Getty Images

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