Romance Report for March 24: Of Marriages and Mistresses

Did Renee Play Second-Banana to Bradley?

Now that it's clear Renee Zellweger's breakup with Bradley Cooper had nothing to do with Sandra Bullock, the question remains: Why did they call it quits? Us Weekly blames a surprising third party.

"If I had to pick any possible mistress, it would be Brad's career," an insider informs the mag. "He worked really hard to get [to] leading-man status."

The couple hooked up just as the actor's career took off with "The Hangover," and Zellweger "had to take a backseat," explains the source. "She traveled with him to make it work."

Not that the Oscar winner, 41, had a problem compromising. "She’s accomplished a lot of her professional goals," notes another snitch. "So Renee took some time out to be a great girlfriend and see if this is what it took to make a relationship work."

Ultimately, it wasn't, so "she stopped fighting" and admitted it wasn't going to work.

Another purported sticking point, says PopEater, was Zellweger's desire to make things more permanent. "She wanted a ring," maintains an insider, "and he just wasn't ready to propose."

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