Its for two reasons.One was she loved him and didnt want him to fall further and the second reason she was doing it for Naruto too as Sai explains a panel before.Because she loved him and didnt want Naruto to be further threatened she decided that she herself was going to be the one to kill himShe wanted to stop Sasuke because sheYou must be registered for see links. Sai was initiate of this bad plan, funny enough, and the struggle between Sakura, Naruto, and Sasuke was causing more strainYou must be registered for see links
She wanted him to acknowledge her.And there are shocking moment when he didnt care about Sakura's life which made her feel very bad about it as the one she loves wasnt giving a shit.That however does not mean that when it comes to supporting the right side she will still choose Naruto,albeit crying, not Sasuke.She also had tears in her eyes when she saw Team 7 working togetherThat's why I said she would try to at least, to gain acceptance. She seemd on the side of wanting to please Sasuke, or to find out if he was at least thinking about her, rather than focusing on the task at hand. Which only brought me to conclude she was thinking about him thoroughly throughout the War. With him there, I feel as if those thoughts and emotions were heightened.