Did she cheat on me?

We weren’t officially together at the time but we were seeing each other, she went out partying with her friends and kissed some guy even tho she said nothing would happen. She apologized for hurting my feelings but says we weren’t in an official relationship so she didn’t cheat She keeps bringing the fact that I’ve flirted with other girls before and says I shouldn’t blame her. Did she cheat?
Did she cheat on me?
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