I can’t tell you how to do it, but I can share how I did it in a very similar situation. It was like an year ago when I finally decided that enough is enough and I can’t deal with a person who used to call me her best friend.

Feeling of being best friends was never mutual and she was very possessive of me from the begining – my best friend or other friends or my now partner who I just started dating back then were all threats to her. She would call me in the middle of night crying or make a scene if I didn’t pay enough attention to her if there was other people around.

I tried my best though, I really wanted to be a good friend to her. Maybe because she had made very clear how everyone from friends to lovers had always abandoned her when all she did was love them and I wanted to prove her not all people are bad and not everyone is going to leave her  – i know, i know I had some serious saviour complex. And part of me was scared of what she would do if I would turn out to be one of those people who would ”use her and then leave”.

For a year I tried to cope with the anxiety after spending time with her or from knowing that I would have to soon spend time with her. I felt anxious to even look at my phone let alone to scroll through social media. Just like you I also talked in therapy about this friendship that was turning out to be very toxic for me – and probably to her too since I started to just ignore her and slowly fading away. There were two times we talked seriously but… those talks made no real difference – she was so controlling and I was so submissive and too scared to really confront her and say that I can’t tolerate the way she treats others and that our moral compasses points in opposite directions.

If you feel like there is no way to tell her you want to end your friendship you should slowly fade away. Starting from social media – not liking her pictures or anything. Then giving very short replies to messages she sends because she probably will still message you. Not answering to calls. Then unfollow and unfriend her on every platform or at least hide her from your feed. And the most important part ; if you decide to fade away, stay away. I didn’t stay away after the first attempt to fade away and long story short ; I was anxious for several months and felt very lost and wrong. Second attempt was succes, haven’t heard from her for a year now.

I also had legit fears of her going on a revenge mode to ruin my life. I know she has attempted to do so for people who have wronged her so I was scared that she would do something (we work in a same field and the social circles are small). At least in a year nothing has happened, nothing that I would know of. But then again I have avoided certain people and places and being ”visible”, so yeah.

I bet your ”best friend” will behave the way she behaves in the future too and eventually other people will see her true character too. So even if she tries to harm you or plot some revenge to ruin your life, in the end there will be others too who will know the truth about her. It might not sound much and it’s not very soothing if she really does do something that ends up hurting you or your life in anyway. But you know the truth and you have the right to tell your side of the story and there will be people who believe you and see what you see.

Courage to you, what ever you decide to do!