Told his gf he cheated, she didn’t believe me,

After my exbf (26 yrs old) (4 years) broke up with me(25), we continued to talk and see each other for an entire year , I’d always ask what this “relationship” was and what it meant. I asked him and he always said “idk” but wouldn’t stop talking to me. I was dumb to be there. I found out he had a gf(23) for a year already and I confronted him. He lied about having a relationship, denied having a gf and denied her (I said her name). I recorded that conversation. I stop responding to him, I waited two months to tell her bc I was scared to do so. I told her via Instagram DM, sent her audio, and screen recordings she believed me immediately even called me and ask a bunch of questions. Thanked me for saving her pain and suffering. She cut him off. She messaged me and call me again for more proof, and she believed me. Then he send me a text calling me out for my “actions”. He told me to take the audio down, she sent it to him so he would stop contacting her. She apologized for doing that because now he was harassing me. And I told her that’s why I didn’t want to do this because I’m scared of him. In the end she thanked me, and wish me well. 6 days later I see she followed him back (his birthday) and blocked me. In the end, I guess she didn’t believe me. She felt into his trap of manipulation. I try to save her, instead it just looks like I was a scorn lover. I tried to do the right thing and it backfired on me. We have “friends” in common so I’m sure he’ll make it seem as if I’m crazy. I don’t really talk with anyone so I guess I won’t find out. He did say his first love was crazy, and I bet he’ll say the same about me.

(He has a type she and I are both girl that are thin, look younger than what we appear to be, never had bfs therefore he was our first, same major, big eyes.)

Honestly I would like to hear what y’all think because I’m in shock she went back with him, even after I showed her proof. Like I wonder if she don’t Believe it or she forgave him. What y’all think happen? And how do I move on from this situation ?