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She didn't even look at me.
Literal
She [topic-は] me [object-を] look [thing/even-ことさえ] didn't-do.
The pattern [verb dictionary]+ことさえ + ない turns a verbal clause into a noun with こと, applies the focus particle さえ ('even'), and negates the result — '(didn't) even do X.' Stronger than the simpler ~もしない. Here 私を見ることさえしなかった ('she didn't even do the act of looking at me') intensifies the slight: not just 'she didn't look,' but 'she didn't even bother to look.' This pattern is common when emphasizing that the bare minimum of an expected action wasn't met.