While you actually seem like a pretty decent Mormon on a personal level, I myself would take the revelation of "I am a Mormon." to bash them even more harshly, and to their face.
This happened to me at work once where I was bashing Mormons, and it turned out the Mormon girl had been standing around the corner, and heard all. When she revealed herself, I just bashed them more, to the enjoyment of all.
This goes for any group I'd rant against though, not just Mormons.