My friend and ex...

So basically i was friends with this guy and also had a crush on this girl who he also had a crush on but he told me he would never pursue anyting with her. I got together with the girl and got into a fight with my friend, after that we didn't speak untill a few weeks ago i contacted him because i heard he had gotten together with my ex (that girl) and i thought they had already broken up but turns out she told him she needed a break while she was shit talking to me about him aswell. So as a normal friend would do i contacted him again with an apology for our fight and sent him the screenshots of her shit talking about him (ngl i kinda did too at that time because i was mad at him for before) he said alright and then some time passed untill now she's into another guy and made tiktoks about him while my friend's still down bad for her. So again as a normal friend would do i told him that she's into another guy, and he got really really mad and started defending her because apparently they talked and she said to him she wasn't into someone else (clearly a lie because why would you tell everyone you like The other one and post tiktoks about that Guy aswell) after that argument he made screenshots and sent it to her so then me and her got into a fight and she told me to mind my business blablabla and i told her to stop lying to my friend. So now both of them are mad at me. What should i do?