(18F 18M) was it all my fault?

I need help. I had this one girl in my class which I liked '18F' '18M' I liked her alot really too much love. We used to talk every day but she always used to say I don't want a relationship I don't want a relationship. But she used to hold my hands n one day we danced in a public road hugged n got a little physical in a theater. Just after all of it which made me think she likes me she left me for about more than 2 months giving me a fucking stupid reason which I could never use to move on. I couldn't move on I used to cry for hours all day everyday for more than a month. I tried to move on but couldn't. So I decided to find another girl that could help me move on ik it's totally wrong unethical but I'm not that mature n I did what I had to. I kissed her without feelings got a little physical too. N here comes the shittiest part. The girl I actually loved came back n without thinking shit i went back to her leaving this girl saying I need a break. Then she left again. What was I supposed to do? Then she came back again and left again. All this time whenever I just got back to moving on she came back n this girl that did nothing got fucked. Fast forward to now. We had a uni trip n the girl the one I liked she's my classmate so we're together in this trip. I kept my phone in my bag and she saw my chats with a freind I share everything with. She knows now. She slapped me once and broke up with me. But the worst luck I have there's this girl with the same name as that other girl I had for moving on so it made a misunderstanding that I had to clear out. I went to clear out and they called the actual saanvi. It's over she told the girl I liked everything we did and I was slapped 7 times. All her friends hate me now and this is really traumatic I have this feeling of not being able to breathe and heaviness in my chest mentally unstable situation.

I NEED TO KNOW. Was it all my fault?

Note : The girl i liked also dated someone online when we were in a situationship. When she left me in November once she had talks with a guy she met on a dating app. She had sexual talks and was going to meet him. One day I caught her sending him the same sexual reel she sent me and by then I had left every girl. She didn't meet her tho.