I'm honestly feeling like the asshole here, so any advice would be helpful.

For some background, I grew up in a mostly normal household with a semi abusive mother who was more verbally abusive than physically. There were physical moments like her kicking me in the back and to the ground for accidently hurting my sister (really was an accident). Unfortunately, my elder siblings, female and male, got the worst of it while my younger sister and I mostly got verbal stuff. We'd be cussed out and spoken down to by my mother, getting in our faces until we shut down and shrank away. My father isn't like that. He's awkward but was always supportive and pushed the value of intelligence on my sister and I. He pushed us to explore and learn. The problem is he always excused my mother's behavior. Every time she hit us or cussed us out, there was a justification. When we got too old to hit, she would go crying to my father to say how horribly we treated her so he'd yell at us for her.

After growing up, our relationship was always strained, but it came to an end December of 2023. After her constant gaslighting and excuses for her behavior, she finally crossed a line and I took a stand. Without going into too much detail, I don't have a relationship with my grandmother (mother's mother) because of things that happened when I was younger nor do I want to have a relationship with her. My mother is kind of a fixer and always thinks things can be talked out despite her temper. I got to a new place and she wanted my address. I clarified she wouldn't give it out where she acted offended and said it was only for her. I gave it to her and a month later I got a Christmas card from my estranged grandmother. I immediately confronted her and she admitted to it over text. She kept trying to gaslight me saying things like "I'm sorry you're heart is so full of hate" or something like that. I sent a final message saying she was now out of my life until I deem otherwise. I blocked her.

The year that followed was strained with letters and texts but nothing else. My family got involved and initially pushed us to talk, but nothing happened. After more gentle communication like her sending me a thoughtful give Christmas of 2024, I was thinking of letting her back in. I then found out my credit took a hit because she had bee using a joint LOC in my name and maxed it out. Side note, she's 100,000 dollars in debt outside of her mortgage due to gambling and bad spending. I worked hard on my credit and called my little sister to help me. We called my father together where he said he'd handle it. The LOC was paid off, but it opened a door that I didn't know how to close.

My little sister ended up confronting my father about all the things I went through and all the things my sister also went through. She went off about the abuse both as children and manipulational abuse as adults. It got to the point my dad said if us girls couldn't fix things with my mother then we were both cut off from him. My sister and I are now cut off from both my parents.

I made the choice to cut off my mother for my mental health, but my sister and father are now colateral damage. Am I the asshole?