Apparently, some anonymous sources are claiming that Rory broke this off during a 3 minute phone call that Caroline initially took as a joke. If that's true, the dude is either very strange, socially awkward, both, or has another piece lined up on the side. If you're "crazy in love" with somebody today and then decide "wait.. this is not working out" tomorrow and you break it off over a 3 minute phone call 24 hours later - AFTER you sent out wedding invitations, something is seriously wrong with someone in that relationship. Just my opinion, but that is really, really, really messed up and weird. Forget about them being a celebrity couple for a minute and just try to process that logic as a rational, normal human being...
That came from a random report. Not saying it's not true, I just didn't put much stock in it.
Having to tell a 23 year old girl in person that you're breaking up with her right after sending out invitations is most likely a dangerous endeavor. Better wear hockey pads. Obviously it's better to tell her in person, but what about the back story? They could have been halfway across the world from each-other. Sometimes you just gotta get stuff off your chest. At least it wasn't by text :D