To be perfectly honest, there was a part of Natalie that really rather viciously hoped it did hurt him to see her like this, because his words were cutting her up inside too. She was starting to think there weren't words in the English language much more hurtful than "Sure, whatever".

"I wasn't trying," she said, having to pause in the middle for a breath, "to break up with you."

She didn't expect that to make any difference. He'd probably made up his mind. But she had to say it, just so that she had. Just so he'd heard it, whether he believed it or not.