I cannot eat "strangers'" food
I actually googled this topic and your description is the closest to what I experience as well. I can eat food prepared by some friends but not by other friends. It's embarrassing because I literally cannot bring myself to eat one bite and have to make up something such as I'm not feeling well or have been on a diet. Also cannot eat most potluck foods except perhaps a food someone picked up from a restaurant such as fried chicken, rolls, or Chinese food. I might eat baked ham if I know who brought it but not from a stranger! Cannot eat most foods at buffets in fast food places. Strangely, I eat at most restaurants but if I see a dirty bathroom or a worker do something icky or even if the table is dirty, forget it. But I know I eat at many fast food places and restaurants without problems. Cannot figure it out but for sure I am not starving! Have tried to recall childhood and family events or others that might have contributed to this but no one thing is wholly significant- maybe more like a string of events over time because I developed this aversion to some foods as a child when mom made my lunches. She smoked and had the cigarettes right in the counter while making sandwiches and I remember gagging to watch her yellow fingernails and fingers touch my food. I started going without lunch and throwing away my bagged lunch as soon as I was out of the house. This subsided after a year or so and I didn't have any problems until the last twenty years;
I'm now 62. Well, just sorry you are experiencing this as well but this certainly hasn't interfered with
99.9 percent of my very happy life, so perhaps shows you can go on in spite of the oddity of it! Thanks for listening.....this has been somewhat therapeutic for me since only my husband and a few friends are aware of this.