I think I just broke up with my Grandma.... Or maybe she broke up with me? Warning: LONG AND RAMBLING!!

Backstory: Nparents and grandparents. Possibly Nsis. Grandma and I took a trip when my newest nephew was born to visit. My sister ambushed me with Nmom (I'm NC) and I witnessed both Sis and mom started the GC/SG shit with the older nephew (aged fucking four.) Gram and I left early but I was a fucking mess the entire 3-4 hour drive. I just cried and tried to explain why I was upset. I begged my grandmother to keep everything I said between us because I knew my filter was not working properly. My other grandma (they go to the same church, was not aware that either had N tendencies until last summer) asked me if I was feeling better about my trip because she heard I was upset. Then my sister randomly unfriended me on Facebook, ostensibly because I had limited her view of some of my own FB page (literally 6 months prior.) I was shattered. Flashbacks for months of SG moments with my mom, pieces falling together of how my mom mysteriously "found out" about things I had told my grandmother but they waited long enough between events that I didn't get it. I woke up sobbing for months jus picturing my poor nephews face, wracked with guilt because I know what he's in for and I can't help without lighting myself on fire. I tried to talk to grandma then but when I tried to tell her how hurt I am and ask why she thought it was ok after promising me numerous times. She just "well okay then, I love you" and hung up. She keeps sending me cards with cash because I didn't cash the checks. So I called today to try to talk to her about this and try to move past in a structured contact way. She kept pestering me for details about my life. I refused and explained that I was too hurt to allow her into my life without a discussion. She tried to cut me off with "I love you" and "come to see me anytime" but I calmly (maybe a couple of tears and a shaky voice but I held it together) explained that I wouldn't be coming to see her. That we could either talk about it and try to move past it or we could be nothing. Her response? "Well okay then, I love you" and hung up on me. I need to know that I'm not going to hate myself for this when she dies. As much bullshittery as I remember, I was her GC and mom's SG so she was one of the only people who consistently reinforced the idea that I am special and loved. I want to go back to before I realized she was the N-momster to my own N-momster. I can't say anything to her without worrying/knowing that she will spill it to anyone that she can lord it over. I feel so adrift. I've cut out almost my entire remaining family members over the past 9 months and I'm facing a shoulder surgery on my dominant arm. I literally can't even think of who to put down as my emergency contact, let alone who I can ask to take 36 hours of their life driving me to surgery and then babysitting me post-anesthesia. I'm terrified of being triggered while fucked up and defenseless because being sick when I was growing up was a "deal with it on your own and shut up about it" thing for me. I'm terrified of alienating the few friends that have stuck by me through all of this by turning into my psycho-mother when I'm too fucked up on pain meds to know better/realize I'm being hurtful. And I have no one to talk to. I have almost gotten to being ok with not having a mom but that's taken 8+ years of NC and I still had my dad, step-mom, Grandmas and siblings.
It just feels like too much, too fast and I'm afraid of going back to their crap except I literally would be killing myself by way of auto-immune disease. I don't know what the point of all this was but I scrolled through 300 friends, family and former co-workers in my phone and couldn't find a single person that I wasn't paralyzed by guilt about dumping this on them. I'm thankful for this place but I really need a mom. Or a grandma. I want someone to hug me until I let go and mean it. Really WANTS to hug me instead of just tolerating it until they push me away saying "ok enough!"