My ex boyfriends ex girlfriend asked me to defend her against him publicly

I'm not saying I will do this at all but you know when you get that feeling to spite an ex. I know this is not the situation to do that though. I'm not sure what this post is. I guess a vent. Me and my ex broke up two weeks ago. I'm not gonna pretend he was a great boyfriend because he wasn't. Guy has a lot of issues he needs to work through and it was toxic. His ex girlfriend reached out to me when she found out we broke up and wanted to shit talk him with me and I ignored her. He had told me that his ex girlfriend raped him. His story was they broke up and decided to remain friends. He deals with severe depression and was struggling with drug addiction at the time. He asked her to come over because he just wanted to someone to talk to because he was talking about ending his life. When she was there he shot himself up with heroin and passed out and woke up to her having sex with him. There were a lot of people who didn't believe him because I get it. You invited your ex over to "talk". If I just heard that story I'm not sure how much I would have believed it on its own BUT she actually was charged. He did report it and she plead guilty in court. That's all documented and public. She messaged me again saying I owe her nothing but since I know what he's like to date can I plz hear her out. I should have ignored her but I decided to hear her out because she felt pressured into taking that plea deal. I know it was wrong. Her story was different. She started off by saying that they had actually gotten back together. And that he lied about them still being broken up and he was begging for her back. She did show text messages of them talking about possibly getting back together but no proof they got back together but her side of the story did end with her saying she did have sex with him while he was passed out asleep from being strung out on heroin. And I told her I can't defend you because at the end of the day you have admitted to being a sober person and having sex with someone who was drugged out and asleep. That's rape. Doesn't matter if he was your boyfriend or not or even if he was hard. You admitted that and admitted that in court. And I do believe his story over hers. Doesn't matter regardless because what she did was wrong but he gets extremely emotional telling it. She was telling me how this has ruined her life and if I dated him I know how he fucks up people's life and be a woman supporting another woman. I would never say he fucked up my life. He made it harder yes. I would never refer to him as an abuser. Was he toxic yes. I think he has unresolved trauma. I ended up blocking her and I feel bad for even entertaining that. But part of me just wants to spite him because I'm hurting. And part of me wants to hurt him because he hurts me but the other part knows that's fucked up. I'm just a mess.