I have some questions. Are you sure he and his gf didn't break up? Does his gf know that he asked you to the dance?
If the answers are both no, then you should definitely reconsider going to the dance with him. If his gf, caught you guys she probably wouldn't be happy. He probably asked because he knew you liked him, or someone dared him to. As for your asst. coach, you can like him, no problem, but take it to realt=ity that he probably doesn't like you(I mean he's 18, no offense.) And besides, it against the law. But if it's a harmless crush, then you can like him.
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