Why is rosalie always so pig-headed?

pig-headed???
wow....
I personally think she is one of the few characters from this book to actually have character depth.
The most probably reason Du hate her is because she loved edward and didn't agree to the fact that Bella wanted to Mitmachen the vampire team?.
...
Im saying it clearly,I would've done the same!.
She was in great pain as we all know from her story in eclipse.
& about the 'thinking she is beautiful,thingy'
Let's take things the other way...
What was Bella's reaction when she first saw herself in the mirror after the vampire-transformation?
She practically even used her beauty later in BD in so many ways.
Rosalie on the other hand didn't want Bella to Mitmachen the vampire family because she felt that Bella would've regret it.
She did,is it so cruel from her to 'advice' her?
because I really don't see the point when Du say Rosalie is a bitch.
...
The rest of the Cullens only like her because she makes Edward happy. That only leaves her parents and her "friends". I do not call them her friends, however, because she selfishly uses them when it benefits her, then dumps them like rubbish and expects them to remain loyal to her. That is arrogant, rude and abusive. Just because Bella feels bad about doing something does not give her the right to do it again. Also, she is completely ungrateful. All she does is whine and complain about how horrible her life is, which it really isn't. However, the people who actually do have reason to complain are seen as whiny if they utter one little complaint. Anybody who doesn't like Bella is automatically a bitch, as well as anybody who doesn't allow Bella to use them.--(last paragraph written Von XDRoseLuvsHP & I totally agree with her!)
My opinion,If Du think Im very wrong GO AHEAD CORRECT ME!and I'll explain EVEN MORE!

--Team Jacob.--<< [i] random:)

part of it is that she really thinks she's prettier/better than others and the other part of it seems to me like a mask to hide her vulneralbility (like most stuck-up girls)