Kristen Stewart FURIOUS That Robert Pattinson Wanted To Spend His Bday DRUNK Without Her?!

We wanna know… why WASN’T Kristen Stewart invited to Robert Pattinson‘s pre-bday booze adventures?!
Even though we thought Kristen had all these fun things planned for RPatz’s 27th birthday, it seems either those plans were BS OR something BAD happened between the pair..
Cause the Twilight couple reportedly spent the entire day apart!
AND not only did they NOT see each other at all, a photog who captured snaps of Kristen in her home yesterday alleges she was agitated and visibly upset. Apprently K-Stew was pacing back and forth while on the phone AND she was smoking cigarettes.
She then got into a car with a girlfriend and they drove around the neighborhood before parking…
And get this, the girls talked in the car for almost an hour!
So, if we are to believe the photographer, it seem Kristen is DEF upset about something, and we’re guessing it has something to do with Rob.
Robbie Rob was spotted the night before his special day looking rather hammered after leaving a Hollywood hotel, so maybe she was annoyed about that? Either because he didn’t invite her or because she doesn’t like him drinking?
Or maybe he DID something that night that warranted a negative response!
Hmm, we are VERY curious as to whether Robsten will show up to Cannes together…
We’re keeping our eyes PEELED like an effing banana!
[Image via Retna LTD.]