Looking for clarity after my sister’s renal failure 🪽

My older sister died last year after struggling with alcoholism for many years. She was only 29. She lived with our insane, also alcoholic, mom (who I cut contact with years ago) for the last year of her life leading up to her acute renal failure. I had limited contact with my sister for the last two years because her alcohol use had turned her into a different person, plus our mom isolated, enabled, and manipulated her.

Being the younger sister who’s spent over half my life trying to protect her from my mom, the guilt and pain are so very real. When I got the call from the hospital chaplain, I had no clue that my sister had been in and out of the hospital (even ICU) many many many times since living with my mom. She had gone to the hospital three or four times from 2020-2022 for pancreatitis, supposedly, that I knew of. Having been so isolated from her, I just have so many questions that I was too traumatized to ask hospital staff and I know I can’t ask my mom. I’ve reconnected with our mom since my sister’s death because I know my sister would’ve wanted that. But she’s used this time to blame everyone else but herself, pick fights with me, and complain about how I wasn’t there for my sister just like i’m not here for her (even though we talk weekly). I’m struggling to set the boundary of creating distance from her again, and I think I really need more insight into what she’s not telling me about my sister’s last year.

Not sure if this is the right sub to post in, but i’m looking for any answers or clarity anyone can give me who’s been in this experience or known someone who has. If she was hospitalized 10+ times, and died from acute renal failure and bowel ischemia, did she know she was dying? She and our mom never told anyone else what was said at those appointments. Was she given specific numbers in regard to kidney/liver functioning? Was she put on an organ donor list or was she told she didn’t qualify? At what point should she have been involuntarily committed? Is there ANY way my mom could’ve lived with her for an entire year and not know she was dying? Or that she needed to stop drinking? Could this have been prevented? Also, why didn’t they do an autopsy?

I have a million more questions that I know will never have answers, but I think these few can bring me some clarity or at least help me decide what the fuck to do with my mom. My sister was my best friend my entire life. I feel intense survivors guilt for not being the one our mom chose. The very least I can do to honor my sister is to be more informed, understand what she experienced, and not feel sympathy for a woman who might’ve contributed to her death.