His Ex Was Betrayed Too

AITA for exposing my boyfriend's biggest secret after I found out he was cheating on me? I never thought I would get to this point but here I am. It all started when I met Jason six months ago. He was charming, sweet, and seemed perfect. We clicked immediately and I fell hard for him. He was my first serious relationship in years and I trusted him completely. Things were perfect at first. We went on romantic dates, he introduced me to his friends, and I thought I had finally found someone who truly cared. But then, I started noticing small things. He was secretive about his phone. He would always hide it whenever I walked into the room. He would get nervous when I asked questions about his day. I brushed it off thinking I was overthinking. One night, I decided to surprise him with dinner. When I arrived at his apartment, I found his phone lying on the table. I saw a message from someone named Lisa. It said, I miss you. I froze. I opened his phone and saw dozens of messages between Jason and Lisa. They had been seeing each other for months. My stomach sank. I felt sick. I wanted to cry, but I was furious. I confronted him right then and there. His face turned pale. He tried to deny it at first but then broke down and admitted everything. Lisa was someone from his past. She was his ex-girlfriend who he had never fully gotten over. He said he was cheating because he felt trapped and lonely. I was devastated. But then I did something I never thought I would do. I decided to turn the tables. I took screenshots of all the messages, packed my things, and left his apartment. The next day, I posted everything online. I shared the messages, the proof of his betrayal, and how I felt. I wanted everyone to see what kind of person he really was. The response was overwhelming. Thousands of people called him out. His friends disowned him. He tried to apologize and begged me to take down the posts, but I refused. I wanted him to face the consequences of his actions. What hurt the most was that he had been lying to me for months. I thought I knew him, but I was wrong. Then came the biggest shock of all. A week later, I received a message from Lisa herself. She apologized for everything. She told me she was also in love with Jason but had no idea he was cheating on her too. She said she had no idea about me and felt terrible for hurting me. I was stunned. I thought I was the only victim. Now I wonder if I did the right thing. Did exposing him help or make things worse? Did I destroy his life for something he deserved? Or did I just hurt myself in the process? I am still processing everything. I feel free but also broken. I do not know if I will ever trust again or if I will find someone who is honest. I want to move on but the betrayal still haunts me. So now I ask you, AITA for exposing my boyfriend after I found out he was cheating on me and for sharing everything online? Or was I justified because he broke my trust? I need opinions because I am lost.