How do I stop my mom from driving me crazy all the time?

So I posted a few days ago about all my mom’s issues and feeling guilty about putting her in a SNF. The comments I got were so helpful. I feel sad she’s in a home, but I know this is where she has to be for all the issues she has.
Mom, in the last month, broke her hip twice (2 falls) and had a major stroke while in the hospital due to long term smoking. She now has sepsis and is on 6 weeks of antibiotics. She is addicted to opioids, alcohol, and cigarettes. She has a personality disorder of some kind it’s in diagnosed but she doesn’t t manipulative, and a narcissist. We are not close, but I am an only child so I’m left dealing with this. Extended family had helped.
She has only been out of the hospital and at the SNF for 3 days now. Yesterday she had PT and the therapist had her sitting in a wheelchair. She said she was dizzy and needed pain meds. She’s not been eating which I’ll get into in a sec. The therapist was trying to get through the therapy lesson, but my mom pitched a fit and he said fine, I’ll get the nurse to help you back in bed. When he came back she had thrown her oatmeal across the room. She said she got angry. She’s worse than a child.
Today she kept texting me SOS. I finally was able to speak to her over the phone and she said no one in the facility was helping, the nurse was In There with her and said she had been in there several times. My mom said she was trying to call for someone for hours. But no one came and that my husband and I should be doing random walk through to make sure she’s being attended to. I told her I did do that before picking the facility and that she had the same problem while I. The hospital and that they have other patients and my mom needs to be patient. She said not I don’t I expect my needs to be met as soon as I ask. I said that will never happen mom, that’s unrealistic.
She is refusing to eat, like anything. Even though we have pleaded with her. I asked her why she won’t eat and she said because she was sick of people telling her to eat. I told her it was just to help her and her body needs it. She said she didn’t care she will eat when she wants to.

There’s so much more, this is just the surface of it. She wants me to drop what I am doing and wait on her hand and foot. She wants me to come to her whenever she asks. I simply can’t. She’s driving me crazy, I hate visiting her but I make myself do it. When she calls I get extremely anxious talking to her. It’s such a mess and I’m trying to teach myself to keep it separate from my life because I have very trying kids who need me and I’m putting them first, by all means, but my anxiety is through the roof.

I am not on anxiety pills I don’t think I want to be. This is all situational. I did have some postpartum anxiety but it was manageable before all this. I feel bad saying this but I just want this to end. I'm mentally exhausted.
I don’t think I have an exact question m, just seeing who else has been through this with a narcissist parent. How did you keep it from getting to you and upsetting you?

Thanks for reading!