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I have a crush on a guy in my school, and I told my best friend about it.
I recently found out that he started dating a girl who happens to be friends with my best friend. A couple days after that my crush's girlfriend (we're not friends, but she's one of the nicest girls in school) came to me at lunch, and told me that she knew that I had a crush on her boyfriend, and that my best friend had told her.
I denied it, but now I don't know what to say to my friend. I told her about my crush in confidence, and she not only told her friend, but his girlfriend of all people!
How should I approach her about the fact that she betrayed my trust?