Just in case anyone is having the same issue I was. I found this in the Curve forum. It was driving me crazy, and turns out IMAP isn't properly clearing Incoming messages in GMail.
Originally Posted by albee 1
From your mail screen press alt-I, alt-O, or the letter V. This should bring up incoming, outgoing and saved messages. Could be a message you saved and never read. If it has not been opened it won't go away until deleted.
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