Such an experience being attacked with 〜目に遭う

Idiom Explanation: Having a bad experience with 〜目に遭う

After an unexpected transformation into a warrior of justice, Usagi learns that her friend Naru is in danger. When she gets to the jewelry shop owned by Naru’s family, Usagi is violently attacked by a mind-controlled crowd.

うさぎ:: 「どうして　あたしがこんな目(め)に遭(あ)うのっ！？」; “Why is this happening to me?”

Key Points

1こんな目に遭う means suffer this kind of bad experience

目(め)に遭(あ)う is used for undergoing something unpleasant.
こんな points to the immediate chaos of being attacked by the crowd.

2遭う fits unwanted encounters

This kanji often appears with accidents, trouble, or harm.
It is different from simply meeting a person; Usagi is being subjected to a bad situation.

3どうしてあたしが centers Usagi’s protest

The が highlights “why me?” rather than just “why is this happening?”