How do you help elders with remote tech support while not being frustrated

I've often gone to this sub to remind myself of how things could be worse, and I should be grateful for what I have. Just writing this into the void because I am struggling. My mom still lives independently but probably won't be able to for much longer. She has a chronic illness and is a widow, and I live a few hundred miles away. I feel some amount of guilt for this, but it is likely she can move up here to be with me when it is necessary. I try to support her how I can remotely, because she does need help. She has some sort of mild cognitive decline and visual processing empairment that doctors haven't been able to figure out- it leaves her struggling to read many kinds of text (books, bills in the mail, login options in apps, etc). It's probably just at the extreme upper end of the range of what could be considered normal aging, but it is likely partially related to her disease.

I was just trying to help her login to Google stuff on her new phone and it was so difficult to walk her through the options over the phone with her visual and minor cognitive empairment. There are about 15 steps it feels like (avoid passkey prompts, enter her login, enter second factor, go to her email, get the code, etc), and she kept pressing the wrong things leading us to have to start over. I started to get frustrated and she knows me better than anyone, so she could hear it in my voice and that made her less able to follow my directions. I think I feel frustration with this tech support stuff, because I start to remember how smart and capable she was when I was younger, and how I looked up to her as the most "street smart" person in my life, who fixed a lot of my problems even in early adulthood. That person is partially gone, and I feel a kind of grief about it.

I have gotten therapy in the past a couple times about this, but still struggle with this feeling of frustration and wishing my mom was the way I remember. I am kind of the first of my peers dealing with this issue (my parents were older when they had me), so I don't have in person friends to talk to about this who really understand. A lot of online stuff is about people in a lot worse situation than me. I try to remember that she is still here and I should be grateful for that. Outwardly, those complex feelings register as frustration, but I want to find a way to manage those feelings because I want to enjoy these last few years with my mom. I was wondering how you all deal with this stage of helping elders with stuff like tech support and staying patient. I could use any advice you have. It's weird because I am a longtime tutor and am often extremely patient, but when my student is my mom, it is a more complicated situation!