I've been curious about this for a long time. I don't understand why Carlisle, Esme, Edward, Alice and Emmett have the last name Cullen but Rosalie and Jasper have the last name. I thought Emmett and Rosalie were officialy married. And I can understand why Jasper is Jasper Hale b/c that was his name pre- Cullens, but why Rosalie?

If anyone can clear this up for me I would really appreciate it. I just wanna know if I'm just being stupid and missing something... :D thanks