Definitely not overly sensitive. You should've probably stopped talking to her after she fucked you over, but I know exactly how it feels to give in and keep talking to her especially since you like/liked her. I'll tell you what you should do though. Stop talking to her now. Take her to the dance then ditch that bitch. Judging by what you posted, she isn't trustworthy. If you got into a relationship, she most likely would not be loyal.
Fuck girls like that, man. I feel for you and wish you good luck.
"Now there are skiers and then there are gymnasts with skis on their feet." - Tom Warnick. The most interesting man in the world. Stay thirsty, my friends.
"She got a big booty so I call her Big Booty" - 2 Chainz
"Nothing in all the world is more dangerous than sincere ignorance and conscientious stupidity." - Martin Luther King, Jr.
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