Great story. Like another person said, just own it. She's seen you in your speedo and if she told other people, who cares. She's obviously comfortable with it so enjoy it. The idea of wearing a speedo without being ashamed is what we all want anyways, so let her talk about it. I might be a little embarrassed if I saw someone I work with while I'm in my speedo, but it is what it is. You're a speedo wearer...be proud!
