Quite. Think you may have hit the nail on the head.
It always seems to be big big news when Dec either gets a girlfriend, or splits with a girlfriend! Wonder why?
Ant and Dec are almost never papped when they're not working, unless Dec has a girlfriend, and then we're treated to lots of shots of them proving how loved up they are.
As someone else has said, there's a real whiff of PR about this - apparantly she's hurt because he doesn't want to committ, but I'm sure I remember reading that he split with another girlfriend because he wanted serious and she didn't.