Feeling FOMO for missing family events where toxic/abusive mom will be

My mom was physically and emotionally abusive to me as a child. I'm now almost 30 and it has mellowed out to some screaming meltdowns a few times/year, and constant passive aggressive comments and criticisms. I took a 'time out' for 4 months this year, and now I'm back to LC. Although I see her at family events almost weekly so it's probably just regular contact at this point. My anxiety is back and as bad as ever, whatever progress I thought I made in therapy and during the break has vanished and I feel like a scared little kid again when we talk or when I see her.

I don't know if I can have a relationship with her, and also heal from the trauma she caused. I'm in therapy and was diagnosed with c-ptsd, attachment trauma, developmental trauma, and some more. Seems a little jargon-y to me but the therapist is working on a treatment plan for me which seems to help with my ptsd symptoms.

The weird thing is that I feel FOMO for missing family events that she is at. I know I don't want to see her, so I don't want to go, but I see my siblings enjoying these events/vacations, and I feel like I'm missing out. She didn't abuse them like she did me, their relationship is really different, somehow it all works for them. I just feel like an outcast in my own family. At an event over the weekend, my uncle came up to me and told me how I don't do anything with my family anymore (meaning my parents, not even with him) and that I'm basically a wet blanket, and that he 'guesses he'll see me in 5 years'. It was pretty rude and abrasive and obviously hurt my feelings to hear it, specifically because I very rarely talk to this man, and the fact that he knew I was skipping events and vacations with my own parents tells me that my mom is gossiping about me to my grandma, and then my grandma is gossiping about me using that info with my uncle. I know this because my mom doesn't even speak to my uncle due to an old long-standing family feud they have.

My siblings, nephew, and parents and grandma are all going on a big family trip this week, and I'm not going because I knew it'd induce crazy anxiety for me and I just don't like being around them knowing there is so much toxicity and gossip among them. They literally rip other family members to shreds with the gossip when they leave the room, and then act super nice and sweet when they return to the room. I don't think it's normal. BUT, I still feel FOMO and am finding myself trying to find a way to attend even 1 day of the trip.

Does this resonate with anyone? Is this crazy? It'd be good to know I'm not alone in these weird feelings.