Anger and unwillingness to help

Hi guys,
I think my mother is a narcissist. Growing up she would she would always talk about how sick she was so she could be doted on by my father.

She would threaten to take her life all the time if anyone did something she didn’t like

She would blame one of my siblings all the time for her depression to the point where my sibling ended up depressed

I noticed she is also emotionally manipulative to those in our communities and even her friends and always says things to make people feel pity or guilt for doing/not doing things she wants

Since getting older, my siblings and I are no longer able to be as easily manipulated and therefore her theatrics don’t work anymore, she has calmed down but now as I get older, I am so emotionally and mentally distant from her. I feel as though she was never truly that maternal and was always so angry. I feel as though my internal monologue defaults in angry as a result of that always being what I hear

My issue now, is she’s getting older and requires help but any time she asks me, I just become so irrationally angry. If it were anyone else asking, I wouldn’t be. I feel bad because her asks aren’t often big but I just find myself irritated even when she’s just speaking. I want to heal and get over this but I just don’t know how to without making things awkward for my father and siblings.

Anyone know how to manage this?