bet I missed the twist....

Just caught this for the first time. Overall I enjoyed it, but it was average enough, I don't feel a need to ever sit through it again.....

About the sisters, their issue etc, and pretty much everything that happened... it was light-hearted enough, that I didn't pay REAL CLOSE ATTENTION... so I think I missed the ending....

Near the very end, they show a beer commercial, maybe the same one our lead girl was in? or maybe just another version of it for fun. it's probably nothing, or everything... was the girl in THAT commercial the REAL girl who "made it in LA", meaning the girl WE saw was the younger messed up sister.... supported by: the identity theft shoved to us, him talking about how all the girls in LA who sleep around have something VERY MESSED UP in their past, how he didnt recognize her at first - she TOLD him who she was posing as her older famous sister?

Just wondering if I missed a twist, since I wasn't deeply engaged in it. Let me know.