Boy did Grey’s Anatomy’s Mark and Lexie hit the skids fast.

One episode, they look like nothing can break them up. The next? They're in bed (or on the floor) with other people. Other attractive doctors we know well, no less.

Mark's reaction to Lexie admitting she slept with Alex was that he can't even look at her anymore. He may never look at Little Grey quite the same, it looks like.

That's because she's going blonde! Check out the pic below:

This photo is disgusting overall. But Lexie's hair looks cute!

Yup, that's Chyler Leigh as Lexie in "Valentine's Day Massacre," the ominously-title February 11 episode of Grey's Anatomy. The show is off this week but back February 4.

Do you like Lexie's new 'do? More significantly, do you think she and Mark will get back together? Or would they be better off preferring other romantic interests at work?

Steve Marsi is the Managing Editor of TV Fanatic. Follow him on Google+ or email him here.