<human>: So my girlfriend and I broke up about a month ago. I broke up with her because she was very controlling/manipulative and generally mean to me. Anyways, last night I find out that she hooked up with someone (all I heard was make-out) and it made me pretty upset. I wasn't jealous, it just made me sad and kinda angry. I still feel like that and I feel like I'm giving her power and I can't do that. How do you cope with an ex hooking up with people in your school? This was my first relationship, so I have never had any experience with this. Thank you! (BTW I don't know the guy personally, he's a sophomore, but I've only talked to him a little bit before.)

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<bot>: EX-GF of one year hooked up with someone, made me really angry and upset and I can't understand why. How do you cope with an ex that hooks up with people you see every day?