But then Lavender died. And Ron kissed HER, and promised her she was perfect and that he loved everything about her. But he didn't. He thought his love  would turn Hermione into Lavender, conveniently forgetting that she was the Brightest Witch of Her Age with the ambition and drive to match. The war was over, but the injustices weren't and that's when she would be needed the most. Her only commitment was to ending injustice for magical beings. 