Just bringing a different view of Sakura's confession write by a NH/SS shipper that I reading a while ago...
"Sakura's plan was to stay with Naruto meaning that she was giving up of the chance to be with Sasuke again one day while leaving Sasuke alive wherever he was, in short she was giving up of her own happiness to be with Naruto and making him happy because he loves her even though she didn't love him back while leaving sasuke alive.. "Saving" the lives of Sasuke and Naruto. If her confession didn't work .. she had a plan B: kill Sasuke, which means that even If she was putting Naruto well being in first there, it wasn't because she loves him but because she felt guilty because of the promise and wanted him to be safe. She just love him as friend but she was willing to be with him to make him happy."
More or less like that .. I don't remember where I read it so I could not go there and and copy the original post.
I mostly agree with this, other than the "not loving Naruto" part. Sure, she was guilty but what's important is that she
still put him before Sasuke, that's not something to take lightly. Her entire concern was Naruto, not Sasuke. She was willing Naruto hating her if it meant his burden was released and he was safe in the Plan B option (which she predicted would happen anyway, given Naruto's stubbornness). The fact that Sakura was willing to do this shows insane levels of dedication and selflessness, it proved that Naruto is more important to her than Sasuke is. Whether her feelings or romantic or not, she
does love Naruto more than she loves Sasuke.
The thing about Sakura is ... no matter the situation, I cannot picture her to lie about loving Naruto. Desperate as she was during the confession, she must know that would've done much harm than good to Naruto. She knows he loves her and if he god forbid accepted her confession, she's practically living a lie with him. If it drags on, all that will happen in the end is that it would only break his heart, much more than the promise. Given how Sakura already feels guilty enough hurting him because of the promise and feelings for Sasuke, she would never do such a thing. Lying about loving someone to someone who loves you is worse than telling the truth.
But if she was still confused over her own feelings ... I can see her doing it. It's not as terrible as not loving him at all and she thinks that she might love him. She wants to, but she's not exactly sure yet. I bet she expected some sort of clarity the more she spent time with Naruto if he accepted the relationship option. However, it seems like Sakura knew it was not as likely as Plan B.
"Loving him as a friend"? Possible, but not likely IMO. Many things like the Hug, Yamato's unfinished sentence, Tenchi Bridge, Feeding scene, and Databook contradict that assumption pretty heavily.