[He wants, desperately, to believe in Xander's conviction about Kim's safety. He's been trying to convince himself, too, that she'll be alright, but-]

...y-you know, she's been- doing her hardest, trying to look out for us this whole time, it's...

I-it's only fair to do the same for her. Thanks, for... for doing the right thing. [His hands start jittering, which he hopes he can just pass off as mindless button mashing.] ...you're- h-heh- you're the genuine article.