Feeling Alone in This (especially on holidays)

I’ve been feeling a little better lately after doing a gut microbiome test and changing some of my diet. However, I have been struggling horribly since Thanksgiving lunch yesterday. My family is aware that I have SIBO and knows some of the foods that bother me. I offered to bring a few dishes just in case, but they insisted that I don’t and that they had it all under control. I got there and every single thing was something that I can’t eat comfortably. I wish I had just not eaten, but I risked it due to being really hungry and have been in severe pain ever since. My dad was offended when I refused seconds (and when I originally offered to bring food). I feel exhausted from trying to tell people that this is not just a little tummy ache or gas. I have been struggling with it for a few years now and sometimes feel so alone in it, especially when things like this happen. I wish it were talked about more and just want to say that I am grateful for this space where I feel understood.