after reading the spoilers as well as everyone's thoughts, i believe that naruto is right. sakura is lying. but not about what you think.
remember sakura's main reason from seeing naruto: the rookie's decided that they themselves need to deal with sasuke, even if they have to kill him. with a decision like that, would that be the first one the chopping block?
but sakura knows naruto wouldnt let that fly since he's been so gung ho on "saving him", despite the fact that he's done kitten that is really screwing up the world. so i think sakura wanted to try to convince naruto to give up on sasuke with the promise of her love, and given how's she spoke, which is pretty genuine. but i think naruto knows she hiding something.
sakura used the truth as a lie.
I couldn't have said it better. She loves Naruto, but it doesn't hide the fact that she is also trying to remove the burden that she had placed on him in part I.