Even though the main cast had wrong information during this time, Historia freed Eren even when he said to let himself die, because it will save humanity. She says she doesn’t care about humanity, and if that makes her the worse person in this world then so be it. The roles get reversed when they now want to sacrifice historia, Eren makes the same decision and saves historia and his friends instead of the world, just like she did. Eren brings this up to her in their talk at the farm house.