That's funny, because he had every right to call her a liar, especially when she looked him in the eye and told him that Sasuke meant nothing to her. That's when he got mad, and that's when he knew that she was lying. He had every right to call her on that from that point forward, especially since her previous actions showed differently. He didn't look happy not one time during that, initially the only thing he looked was shocked.
She's the one that brought the welcoming committee to greet Naruto, the situation embarrassed him just as much as it did her, especially because everyone else there knew that she was lying, they all had the "wtf are you saying?" face on. Sai straight up told Naruto what Sakura's real feelings were, confirming everything Naruto said.
Showing fear for the real reason he was being hunted by the Akatsuki is different than showing romantic interest. Showing concern is not the same as showing love. He told her not to worry about him, he didn't shut down any romantic sentiments from her to him.
So in other words, Sakura is a big fat liar about everything and should have kept her mouth shut and let him and herself go on suffering because they think they know what the other one's wants and intentions are.
Okay then.
Sorry, but I disagree. You can sit here and feel bad for Naruto and think Sakura got what she deserved, I don't care. I don't feel bad for him about this AT ALL. Sakura was doing what she felt she had to do to protect him. She said what she said, and maybe it was clumsy but she MEANT it and Naruto had no business calling her a liar like that. None.