She tried killing Sasuke because he became the opposite of her perfect fantasy. Sasuke is a mentally traumatized boy who is fully immersed in the evils of the shinobi world, his only redeeming quality in the eyes of Sakura is luck of having good looks, being "cool", and having an advanced lineage.Sasuke was not Naruto best friend, and don't use titles on someone like Sakura. Sakura loved Sasuke more than Naruto could ever know, and she was willing to put him down for the greater good.
Sakura did manipulate his emotions, but it was to save nAruto the burden of chasing Sasuke so that he would move on with his life, Sakura noted that Naruto was getting everything he wanted , he was being noticed, he deserve to live in that happiness than to try and save Sasuke
Sakura didn't love Sasuke, she loved her personal idea of who Sasuke should be.