I read the OP and just responded to this without reading everything else yet, so forgive me if this has already been covered...
As someone with a self-imposed limited diet, I am tired of always having to defend myself. I am a vegetarian and mostly vegan. My reasons for not eating meat were just because it grossed me out as a kid and I am a picky eater. Now, my health issues have made me cut more things out.
At a restaurant, if someone asks for a dish with no brussel sprouts, no one blinks an eye. If I ask for a dish made without chicken stock, suddenly I am forced to defend myself against a wide gamut of political beliefs that have been assigned to me. I care not for the animal's lives, I could give a shit about the hormones pumped into meat. I simply don't eat what I don't like. I've never preached a word of my "beliefs" to anyone but yet I am combated constantly. People assign arguments to me and force me to argue them. It's fucking annoying.
Why does anyone give a damn what anyone else eats? Just eat your own food and mind your own damn business. The militancy goes both ways and it's annoying, on both sides.
Ok, I'll read the rest of the thread now. /rant
EDIT: Sorry - didn't offer any advice... I simply tell people to live their lives in whatever way will make them happy and allow me to do the same. Basically, that's my polite way of saying FOAD before I actually am forced to utter those words. Simple.