I've had people ask me if I pregnant before, I tell them I'm having a strongbow baby, that usually shuts them up.
What annoys me is people assuming that I'm not fit because I'm big. I can run rings (literally) round most the people I work with as I actively work out 4/5 times a week and I train hard.
all people can have body insecurities whatever the size, the media has a big part to play here, constantly forcing images which are often photoshopped of how you "should look".
When i first started at the gym, i found it really hard going from pool to changing rooms or being in the spa, as i would be in my swimming costume and I'd always have a towel handy, I don't bother anymore - i'm not any less selfconcious, i just don't really care what anyone else thinks, like me as I am or don't.