Even though she lied to me, I don't hold it against her because she apologized sincerely.

hold 在这里是动词，意思是"保持、持有"。 it 是代词，指代前面提到的"她对我撒谎"这件事。 against 是介词，表示"反对、对抗"的意思。 her 是代词，指代"她"。 hold it against her 是一个固定短语，意思是"因为某事而对某人怀恨在心"或"因此事而责怪某人"。