OK, I understand her being physically repulsed by him and not wanting to have sex with him, but aside from that, why does she dislike and mistrust Tyrion so damn much? Throughout ACOK and ASOS she never seems to consider Tyrion as an ally, writing him off as just another Lannister who wants to harm her. During the wedding she refuses to kneel for him in order to humiliate him, all her thoughts about him consist of him being an ugly Lannister dwarf and nothing more, etc.
Considering that it is completely clear that Tyrion does not belong on the same category as Joffrey, why does Sansa see him this way?
He risked Joffrey's wrath and punishment when he chastised him for having Sansa beaten, which there's NO WAY he would have done if he was Joffrey's/Cersei's patsy, constantly bad mouths and mocks Joffrey and Cersei in front of Sansa, and offers Sansa protection multiple times. Plus, he actually used his authority as Hand of the King to end Sansa's beatings.
Yet she refuses to see that he in fact wants to help her, and that he hates Joffrey's and Cersei's guts as much as her. How can she believe all that when Tyrion is obviously trying to help her?
Hell, the way her POVs are written, she doesn't even seem to realize that Tyrion is actually risking his life to help her.