All the stories say it's mutual blah blah blah. My guess is Megan Fox, whoever she is, looked in the mirror one day, looked over at Brian Austin Green, looked back at her reflection and screamed "WHAT THE HELL AM I DOING??? Daniel Craig is in my top five and I actually have a chance at sleeping with him."
Incidentally, a group of us were staying at a hotel in Arizona years ago and Ian Ziering was a guest at the same establishment. You'd be surprised at how unamused he was by people screaming "Hey Steve Sanders!!!" at him all weekend.
PS -- Was Mr. Walsh strangely sexy or was it me?