I know you're angry, but I would approach your chapter in a calm manner. Tell them you are very upset and hurt that they would treat you like this. Explain that after the Toronto formal was cancelled, you tried very hard to put a nice semi-formal together, and the fact that people walked out AND didn't pay you back is insulting.
If you come off as pissed and b*tchy, you're going to look like the bad guy.
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AGD
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