Anxiety-- even about NON-FA stuff-- can really cause eating problems, even if it isn't technically an eating "disorder" by DSM standards.
My DD really struggled with anxiety-fueled food intake issues for much of the 18 months following her last severe reaction. The months leading up to the (recurrent) event at the 1yr anniversary were
the worst. We were seriously scared for her. This self-resolved when she was able to face down that recurrent event (similar circumstances as the one that caused her reaction, but thankfully different location, since that would have been too, too much for her, I think) using her self-selected means of maintaining
control over the outcome (less fun, less 'out-of-control' age-appropriate kid stuff, more sticking to business, serious attention to surrounding, forgoing shared touch-surfaces, etc). What helped, ultimately, was
getting through the repeat without incident. I wanted to offer that as a way of reassuring you that if you take precautions
and get through the event/gathering without incident, that may go a LONG way to alleviating your anxiety. This was a much more potent affector than we imagined, honestly.
Professionals sometimes, I think, underestimate the power of an anaphylactic reaction to elicit PTSD and diffuse generalized anxiety.
I hope that you'll do as Ra3chel suggests and keep looking for the right professional to really
help, rather than shrugging at it.