Humans have done inhumane things over and over-to nature, to the gods, to San as an infant, and to each other. Ashitaka doesn't take her animosity personally and rather seeks to reach her through softness, by showing his humanity. She sees any human as a threat, including Ashitaka. She does not relent in trying to protect the living beings and the home that the forest creates. San is entirely justified in her sense of urgency when it comes to protecting her family and neighbors.