I LIKE MY FRIEND’S BROTHER advice needed

okay so I have had a crush on my good friend’s brother for quite some time. Around December 28th, he added me on Snapchat and we started talking. At this point, I didn’t think my friend would mind. Then, I went to her house for New Years with our group of friends. I really hit it off with her brother and he seemed to really like me. We started talking on Snapchat everyday after that and he asked me on a date and I said yes. On January 7ish, my friend texted me that she was uncomfortable with me flirting with her brother and I told her I understood. I also told him she said that and that we couldn’t talk anymore.

I got really sad not talking to him though because I had developed strong feelings for him so we continued to Snapchat but I turned him down when he asked me on dates telling him we needed to talk to his sister/my friend first. I was so scared to tell her that I waited a month to bring it up to her. I finally told her and she didn’t react well. I wrote her a super long message about how much I cared about him and how I hadn’t felt like this towards anyone (I’ve never had a boyfriend but wanted to date him) and told her I would respect her decision. my friend got mad at me and told me I couldn’t talk to her brother anymore so I stopped but she still refuses to be my friend.

Her brother even texted her telling her that I’m the first girl that has made him smile since his ex and he completely forgets about her when he talks to me (they had a messy breakup that really hurt him.) I don’t talk to him anymore because she asked me to stop but I miss her brother so much. I have cried multiple times each day because I miss him so much but I don’t think my friend will change her mind.

I’ve never felt this way before so I guess I’m just looking for advice like if I should let him go or talk to my friend about it. I want us to remain friends but it’s hard because she’s refusing to let me date her brother.