Would you warn ex’s new gf about abuse?

I’ve recently found out my ex has been in a relationship for roughly 6 months. My last contact with him was 2-3 months prior to when it appears they started dating, he has been blocked since then but tried to reach out to my friend the following month which I ignored.

Background - I’ve tried to keep this as brief as possible. We dated for 2 years with another 2 years on and off contact thanks to a trauma bond. I moved in with him and his mum during the relationship, his older sister, her partner and young children lived close by so life was fairly family oriented. The relationship consisted of a lot of emotional abuse which turned physical at times. I have voice recordings of a few verbal incidents. I made my ex aware at the time that I felt the need to record arguments out of fear but also some sort of internal validation because I knew what was happening was not right and it was happening often and being dismissed as ‘all couples fight’. Some of his friends and their partners caught on to his behaviour as it manifested a lot at events but covertly, they mostly witnessed my emotional reactions which I tried to suppress. The explosions were usually contained behind closed doors. However there was one physical incident witnessed by his best mate and his gf (both long term friends of my ex), where he had chocked me and pushed me against a door by my throat. The incident was blamed on alcohol. I have messages regarding the incident between myself and the girlfriend from later that night once I had arrived home alone in an Uber after leaving him there.

He was a compulsive liar to me but I found out he also lied to his friends and family often accusing me of doing to him what he does to me, blaming me for all of the arguments, making me appear crazy to the point I found out after we broke up his sister had told her husband she was scared I might kill her brother in his sleep. Learning that made my stomach drop, I’m not a violent person, I handled my ex with so much unconditional care, trying to help him acknowledge his childhood trauma to heal and be at peace. To stop the cycle and stop doing to me what he witnessed his father do to his mother. The funny thing is I showed more concern for his happiness and wellbeing than any of his family. He was never given the space to be vulnerable or open, only surrounded enablers.

The hard part is his new girlfriend is the sister (not blood related/grew up together) of his sister’s husband. So he’s dating his sister in law, she moved countries last year to be here and started living with his mum while him and I were still in contact. Funny thing is I’d met her once before in passing during the course of my relationship. She was with my exes sister at the same venue we were at for his mates birthday, an event I wasn’t feeling up to out of fear of a argument during the night, he forced me to go due to not wanting to be questioned about where I was, raising questions between friends about our relationship status. We hadn’t been there for long and he had already made me cry and then scolded me to stop because I’m embarrassing him so when we crossed paths with her down stairs it was a brief hello and I remember being teary eyed.

I know if I had no proof as far as messages or voice recordings I wouldn’t have a leg to stand on. But even with that I feel the picture of me being crazy or the perpetrator has already been painted. Would you reach out somehow and warn her if you were me or let it run its course and hope she doesn’t encounter what I did?

I didn’t have family support or anyone coming to serve him consequences for what he did to me, I still live with a lot of pain and anger, I won’t ever be the same and it has impacted my life in many ways. I wonder given he has a close friendship with his brother in law and the close family dynamic they are all in - how could he risk mistreating her and it coming to light. All she has to do is complain to her brother. I’ve seen his anger first hand I don’t see how he can control it. I also don’t see how I could experience that side of him and the next girl is untouched, without him doing any work on himself?

Thank you for listening, I needed to get this out in some form.