It runs in my family and I met a guy ( past good friend) who used to have it. I take it you have a card with you incase of emergency. It's very rare, and not often does anything bad happen, but beware general anesthtic etc, as this is not good for a sufferer as it's allergy based.
Not many nurses know about this but doctors are well informed. Talk to them about it, as you say it's very rare, so they deal with this disease text book style. It is life threatening, but we are all okay, my bro's and sisters also and we have had general.
No there isn't much support out there, I agree. Speak to the doctor and ask about councelling to help you feel better in yourself.
Take care, and good luck sweetheart!