It’s a difficult conversation to have for sure. One of two things could happen. They understand or they don’t. Because it isn’t something that happens to them. They love foods and spices. Perhaps that candle smells so good everyone should enjoy it.
The fact remains that after we have talked with them and explained what happens and some will be very interested and others will not.
We love our families we want to enjoy our holidays with them. However when we go it’s over whelming with all the smells and foods we are not able to eat.
I’ve lost 98% of my family members because they don’t believe or won’t give some consideration to my allergies.
The best we can do is explain. We are not able to change their mind. They must take that responsibility
Just do your best. If they choose not to respect your allergies then I guess text or phone calls are the next best thing.
I truly am sorry for anyone who has this issue. Ultimately it is your family’s choice and yours.You can bring your own food. That’s a choice. However if it’s fragrant smells stay away.
I wish luck.

How devastating an allergy is and what affect it actually has on the body

Cross contamination from improperly cleaned and sanitized cutting boards
and other kitchen tools. This is why I refuse to eat anywhere than in my
own house.
And
Air borne allergens from cooking, especially deep frying, that carries
throughout a building and adjacent connected buildings and buildings that
use the same air handling system. Real life example: P.R., who is allergic
to fish,arrived at her church to attend services. Fish had been fried in
the adjacent building 2 days earlier. As soon as she stepped into the foyer
of the church, she had a severe allergy attack. She immediately went to her
car and sat there until she was well enough to drive.

Having people try to shame you because you refuse to eat something they made is not unusual for those of us with food allergies. Example: I baked a cake from scratch for you. It's safe for you to eat. Did you use baking powder? Yes. Did you check the ingredients before you used it? No. I have to assume it has corn starch in it. (Corn is one of my allergens.) Sorry, I can't eat your cake.
Others don't realize how easy it is for an allergen to sneak into food.

Most people think that those who have food allergies are allergic to peanuts. But there are so many other foods that cause problems and it seems like more come along every day. Some a "normal" person would never believe could cause the reactions.
My eldest is just like my hubby and me and is allergic to all shell fish. He lives in Maryland...just outside Baltimore....and it seems that all the restaurants put some sort of shell fish in every dish. Plus they have cross contamination
Tim has learned to eat Arby, McDonald's and other franchises because it seems these are the only ones who don't have shellfish. That and TGI Fridays which does have the shellfish but not in each and every dish.
Good thing I taught him to cook or the poor guy would either be dead from reactions or starve to death