The year's biggest breakup has yet to be officially confirmed by either party, but there's talk of more reasons behind Justin Bieber and Selena Gomez calling it quits. How do pals rationalize the split?

A source close to told Hollywood Life that Selena, 20, may have been too mature for Justin, who just turned 18 in March. “She is way too mature for him,” the source spilled. “He wants to have fun and be young and wants her around all the time, and she wants to be like his mom and not go out and wants to actually settle with someone -- and she is boring!”

While we don't know if we'd call Gomez boring, she is rather mature. This is a Disney starlet who has had no scandal whatsoever during her career, much unlike her peers Miley Cyrus and pal Demi Lovato. Even Taylor Swift has ruffled more feathers, and T-Swizzle is America's sweetheart (or America's psycho ex-girlfriend, depending on who you ask).

Bieber is also pretty well-rounded for a guy who came of age in the spotlight, but it's important to remember that guys and girls mature at different rates -- and that two year age difference may not have been a big deal when the pair first began dating about two years ago (when he was 16 and she was 18), it may have expanded with time. Others have pointed toward Selena's "trust issues" with Biebs for the split.

Either way, we're sure we'll hear more about it on social media!

Watch the Justin Bieber 'Beauty and a Beat' Video

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