Firstly, Caroline didn’t think that Klaus would comfort her. She didn’t expect it, didn’t turn to him looking for it. In fact, Caroline wasn't even looking at Klaus nor was she even focused on him at all when the realization of what she had done hit her. KLAUS is the one who reached out and took her shoulders. He used a soft, comforting voice and said "Hey!" getting her attention, making her look at him all the while he was looking at her with sweet, understanding eyes. He said "you look like you could use some comfort?" in that same soft, comforting voice. Then again, barely even registering, Caroline nodded, and then he delivered his "go find someone less terrible to relate to" comment.
And going back further, there is a lot of justification for Klaus' put-down because Caroline flirted with Klaus, drank champagne, etc. and now she’s being all mean to him. The question seems to be: "What does she expect?" The thing is that this isn't the sequence of events. Yes, Caroline did flirt with him, did drink champagne, etc., but that was all because she owed him a favor. Did she enjoy herself, find herself liking him? Yup. Which is why when she talked to Stefan later, she admitted that she wanted to believe that Klaus had the ability to change, to be better.
Yet at the very time that she was allowing this possibility, Klaus had just killed 12 hybrids, and then for no reason other than that he was upset with Tyler, he killed an innocent woman, Tyler’s mother. *THAT* is why Caroline turned against him so completely. That is why the flirting, champagne-drinking, etc. don’t matter anymore. She thought she saw a better side to him and then he completely proved her wrong.
She hasn’t flirted with him, she hasn’t pretended to feel something she doesn’t, she hasn’t played any games with him since then. Did she tell him that she believed he could be capable of love while in Elena’s living room? Yeah, but she was also on death’s door—thanks to Klaus—and he was literally the only thing that could save her life. But even then, she didn’t go overkill, she didn’t flirt with him or try and promise him feelings of love, desire, devotion, etc.
Being bitchy and not so nice to him, telling him how terrible he is, since everything happened makes absolutely perfect sense. There is a before and after at play here. Caroline gave Klaus the benefit of the doubt, bought into the wounded soul/besotted suitor role and so flirted, etc. That was before. Then he killed the hybrids and Carol Lockwood, then he staked her, bit her, taunted Tyler and Caroline over the fact that she was going to die, then said he was still planning on chasing Tyler down to kill him. That was the after.
Klaus *is* terrible. And he’s shown pretty much zero remorse for his actions. Once Caroline was given undeniable proof that he’s terrible and has about zero remorse for his actions she no longer wanted to flirt with him, no longer liked him. She didn’t want to drink champagne, or spend any time with him, go to him for any reason.
So going back to the specific incident in the last episode, she didn’t go turn to Klaus. Stefan called Klaus to where she was. She didn’t ask Klaus for comfort. She didn’t think it was coming or expect it. Klaus dangled comfort, given with vulnerable eyes, a soft voice, comforting hands, to a distraught teenager who had just committed an unthinking, horrible act with tremendous consequences… only to spitefully refuse to give the comfort that HE had just offered.
I am SO Team Caroline.