I remember lurking in the original thread, but I don't remember if I commented or not. My mom too thought I was gay for a while. I think I convinced her otherwise, because she hasn't brought it up in years. Quite honestly, I fit the profile well. I'm a bit of a mama's boy, along with other things like not showing interest in girls, always hanging out with other guys, took drama class in highschool...
Each has it's own explanation though. My mom is probably the nicest person I know from a completely objective standpoint, attractive girls almost always have an extremely ugly personality, which is a HUGE turnoff for me (and I'm not asexual, but I'm not driven by sex to begin with), the guys I hang out are just close friends that I hope any other straight guy would have, and "the arts" were required electives in HS for me, and since I suck balls (no pun intended) at any crafting type art (Painting, clay modeling), drama was pretty much the only way to get those credits.
Discussion topic: I don't remember my parents spreading lies about me, or inappropriately timed comments. If they have, it was long ago and I wasn't horribly scarred or offended by it.