To which part of her identity is nods referring when she says that “my identity seemed to hurtle towards me and my paste itself right in my face”

I would say she is referring to her racial identity.

She is talking about how people used to be very racist towards her because she is part Japanese (she is a Japanese-American citizen). Just by taking a glance to her face, they would assign her a certain race and treat her differently based on that. 

i think you should write from the heart and think what truely makes a hero. i can’t do this for you. even though this is it’s up to you.

- the mistakes that have been done in the past will repeat themselves

- you will trust all the wrong people