Can someone help me with this guilt?

Hi all. I'd love someone with experience of the fear and obligation to help me to rationalize my situation.

My parents really failed me emotionally. Dysfunction, emotional neglect, parentification as kids, invalidation and gaslighting as an adult. Most recently it was apparent at my wedding. My mother was in no way useful or involved in the planning, she criticized my decision to have a secular ceremony, she criticized my speech on the day, she gave no compliments, was absent at important events (first dance, cake cutting) and was more concerned about how her own siblings felt about my wedding than her own daughter.

It's all hit me recently as we got our official wedding pictures back, and there's nor one photo of my mother supporting me, smiling at me, embracing me, expressing any loving action towards me at all. She scowled through my speech and spent all her time with her own siblings. I've been working through the grief in therapy for a while now and am VLC. Do not all, only respond to stuff and greyrock.

Here's where the struggle is. She calls me occasionally. Like yesterday. I did not pick up. I decided I would "deal with it tomorrow." It is now tomorrow. No part of me wants to talk to her, it hurts me too much. But the guilt is so strong. She is old - mid 70s. I can hear her frailty in her voice. She's slowing down. She doesn't see her own neglect of me. I know the tables are turning and she needs help now. I'm working hard on my own self concept and see myself as an honest, kind person with integrity. I want that to extend that to my parents. I want to be strong enough to accept her as she is and show up with integrity, help her and talk to her because it keeps me in my own values. But it also hurts me a lot.

How do I get passed this? Had anyone managed the complexity of this? Has anyone managed to maintain surface level contact in order to maintain their own integrity?

Any insights or advice would be so appreciated x