I am getting better at it. And I think most of that is down to my response, and most of that I credit to reading about how people on this board handle things, so I treasure posts like yours to get new ideas.
I am off.to my in laws tomorrow, and taking my own lunch and snacks. I don't yet know if we are eating there or at a restaurant,, but I know I will be eating safely.( last time we went, one family member gleefully turned up with a gluten free chocolate cake. I wouldn't eat it, but asked a few questions, and it was made with almond flour. My son has an anaphylactic allergy to almond. Other people just don't get food issues and I won't take the risk. Makes me sad I can't safely leave my son with his grandparents or aunt. But that's another story).
My own silver lining is that as I cook my own food, I always like what I eat:)
I hope you have a lovely evening when you go ahead. Don't be afraid to chase the invitation if it takes a while, I think we end up having to be super reassuring to people sometimes