How to deal with a narcissistic mother?

My mother has no other children and has been diagnosed with cancer. When I was little, he used to beat me for no reason, and not just any normal beating. Even if she got angry at someone, I would be the one to punish him. As the years passed, I grew up and years later I gave him another chance but she never changed. (Let me say in advance that my native language is not English and there may be spelling mistakes)

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1 y
Now he can't beat me but he insults me. And I'm tired of this shit. What should I do?
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1 y
Pardon shee
How to deal with a narcissistic mother?
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