@Avi K. I did ask a Rav at the time, and for that specific person I was able to mekeil, but there was other people in the area who were also involved and I was not allowed to eat their food. Even if someone gets insulted there’s a limit to be mekeil, let’s say the situation was with co-workers who claim to keep kashrut, you have no idea to what degree, how well they keep things seperate or what hechshers they use.
@Avram, there’s plenty of crying citations too. Between brothers and sisters and families who have more frum or less frum family. There are also faily members who may have been born FFB’s like you but are not religous anymore etc…