Even Sora says it might have been a lie. Riku had been using the name of Roxas' Somebody to manipulate her. To get her to hurt her friends and kill herself. Her head came up, and even with the hood it was plain to see that she was furious. It was in every inch of her small form.

"You're right. What matters is Riku."

It was too late to help Roxas and Axel. They'd forgotten her already. This was Roxas' Somebody and he didn't know who she was, which proved that Naminé's spell worked.

Which meant there was nothing for her to go back to.

"I am going to find him, and then either I will end him, or he will finally get his wish. But this time it will be his Keyblade that kills me, not Roxas." She looked up at him. "I will not let him use you or hurt you like that again."