How do I cope with my brother’s toxic ex turning my niece against me?

It hurts so bad how im the bad person now. She keeps turning my niece against me. She doesn’t want my sister to even talk to me. The kids aren’t allowed around our family. He isn’t allowed to see the kids unless he can see her. He has to be with her to see the kids at all.

She treats me like total shit. A few days ago my brother put on a Ty Rex costume for my nephew birthday party. All the kids had fun but she didn’t appreciate anything. She had him nowhere in the pictures except for the costume. She wants no family members talking to me.

She takes all her frustrations out on me. She wants the world to completely dislike me. My niece graduation is coming up and it’s a problem.

How do I cope with my brother’s toxic ex turning my niece against me?
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