Advice badly needed.

For context i have been NC for about 7 months ish. During these times i have seen a few flying monkey. The latest one is my brother's GF. We do not talk much, but the last year's chat was when she asked me to send about 1000 usd/month to her. I blocked her FB and Wechat. Last week she found my email, so she emailed and chatted me on google. This time she demanded for me to resume contact with AP.

The problem is when i brought this up to my brother via phone. He does not want to hear anything about his GF being wrong and accused me of badmouthing her. I am not super close with him and he just think i am instigating negative conversation, when i am trying to protect myself and my boundary. I need peace and quiet and would like to be left alone.

Fyi i am not sending any money.

I want to send an email to my brother asking him to respect my wishes and telling him that his GF should discuss any big requests with him first before solo asking me alone.

The last contact with her caused me so much emotional turmoil and waste a lot of my time dealing with it.

Do you guys think i should send the email? And how can i prepare myself for negative outcome?

I am going crazy because so many flying monkeys are coming my way and considering changing my name because of this.

Appreciate any advice you all have.

Edited (some spelling): What I hope to get from sending the email to brother is to explain that his GF's requests are no small matter. Not only it is money related, she also meddled in a sensitive affair. Also to suggest a solution: instead of the GF reaching out to me solo, they both should discuss the matters first, then my brother can reach out to me if they need financial help, etc.