Caroline never realized it was possible to love and hate someone so much at the same time before the night she was captured and tortured.
Finding out that Tyler was capable of standing there and watching as she and Stefan and Damon were about to be killed made her hate him more than anything, but it didn't change the fact that before she was taken, she had loved him just as much.
That experience just made her realize that Damon and those who came before him were right. Werewolves and vampires could never be friends or lovers or anything. They could hardly exist on the same planet without trying to kill each other.
He came to apologize that night after it happened. He said he didn't know they'd use her, but it didn't matter to her. They had, and he hadn't done anything. Then Tyler walked away with Jules and she hasn't heard from him since.
Thinking on it, she finds herself comparing them to Romeo and Juliet. The only differences she can see are that he had a choice to leave—that he didn't stay and fight for her—and that she's not going to kill herself for him.