Why should I behaviour like if she was a real person not controlled by Kihimoto? She IS one. She is not, was not and will never be real, so it is makes no sense treating her like one. Her actions, thoughts... will ALWAYS be controlled by another person, so that you will alwyas have to factor on it.
I think that in one scene of Who Framed Roger Rabbit, Jessica Rabbit says: "I am not evil. I have only been drawn like this."
Anyway, I always liked Sakura, even back in Part I when people comdemned her and lambasted for being an inmature twel-years-old (a teenager inmature? Stop the presses!). I find the last developments deeply dumb, nonsensical and out-of-character, but I will not hold terrible writing against her. If the creator decided forgetting his own character is it his blame, not his character's.
After all, if we are to condemn her for that, we should be condemning all characters in Part II, including Naruto.