Hey... I can totally relate re: waiter. I had a similar experience, you can read about it here under "Raw Ordeal":
http://blog.myspace.com/simplyzen_rawgurl
I agree with The Vej about true friends. I'm rarely with a bunch of people I don't like... most of my friends are VERY supportive and try to find restaurants that can accomodate my lifestyle.
To avoid such scenarios with friends/family, a sense of humour goes a long way, and I just try to avoid eating with people that may give me hard time. Less hassles.