How do I estrange from my south Asian family?

For context, I’m 18F and my family is very traditional. My dad has been abusive for most of my life, and while my mum tried to support me and my siblings, she’s also very focused on gender roles and maintaining a “perfect family image.”

Growing up there was always some type of abuse in the house, whether towards me, my siblings, or my mum. Even as a kid I remember telling my parents I never wanted marriage because of how their relationship looked to me.

I’ve also experienced SA from my dad since I was 4. Whenever I tried bringing it up to my mum, she would mostly stay quiet. My dad also used to be physically violent, although it calmed down after a police report was made against him. Nothing really happened because my mum didn’t want to give a statement.

The difficult thing is that I still feel emotionally attached to my mum because I know she went through abuse herself while trying to protect us. But at the same time, I’ve lost a lot of respect for how she handles things. She refuses to leave him, says she still loves him, and is extremely focused on appearances/community image.

She also strongly believes girls should marry young and has justified relationships between teenage girls and much older men. She’s told me that if our family became “broken” through divorce, nobody would want to marry me, and that I’ll stay with her until I eventually get married. She also doesn’t want me moving out for Uni and threatens to marry me off for trying to seek independence or if I do bad in my final exams.

I feel guilty for wanting to leave because I pity my mum, but at the same time I feel disappointed.

My mental health has gotten really bad because of all this I feel so trapped in my own mind it's killing me.

Since I’m now 18, I want to know how people actually begin estranging themselves from family. How do you deal/manage with the guilt, emotional attachment and actually leaving your family?