Is it just all in my head? What should I do?

Hello, this is my story:
I met that guy several times at my university, it started 3 ears ago with an eye contact, and then I found out randomly his facebook account and I sent him an invitation. I was into someone else at that time, and it was really toxic( I was single but act as if I was with that person), but that guy,let’s give him a name Tom, Tom was my sunshine because when we cross in the streets he always smiles at me.
There’s a time we talk in messenger but as sometimes he took much time to answer I didn’t reply anymore so we are like off and on… Then I finally had the courage to get out of the toxic situation and begin to heal, that time I met Tom again at the Uni, and week later he texted to me and we talk all the night , he told me he is interested in me but as he just get out of relationship he doesn’t want a serious connection, and for me too I just wanted to have fun, so we make the agreement to just have fun and stop if we find someone that we love.
So I went to his house and we had fun( we did the preliminaries because I don’t want to have sex directly as I told him because I have never had sex). During that time I sense something weird in the way he treated me: he acted more like a boyfriend than sex friend. So I was afraid that he just used me to forget his “ex-girlfriend”. Then I get distant, also because of my toxic past I am not really good with expressing my feeling… He tried his best to get along with me but I avoid him and then everything felt apart….
So I bring my courage and told him that I felt something for him, he answered me that he is going to be with someone else so I need to forget about him, I told him it’s okay, but the way he reacted was he tried to approach me again and kiss me in front of everyone (because in his head the fact that I avoid him was because I am with someone and cheated)and I was confused…
So I approach him and text him and he told me that he is with someone and I should stop, he unfriended me and blocked me… So during 4months we didn’t see each other , then I found out that he begins to have multiple sexual partner, I thought it was my fault…. We met again but I have a feeling that he wants to make me feel jealous and I always try to text him and explaining myself because I thought it was because I avoided him… It was hopeless so last December I moved on*, and on January we meet again and we talk again and decided to have an appointment to explain ourselves, I was 10min late, and I don’t know if he came or not but I didn’t find him…however the next days he was totally angry and when I try to ask him, he told me that there will never be us… So I told him what I really fell and he blocked me again…the next days he tried to approach me but I avoid him because I had enough of the confusion
Two weeks later, I saw him with someone and his reaction makes me confused because when he saw me he directly act like he is just like just friend with the girl, I was broken that day so I decided to forget him….During the lockdown in march I don’t know if it is just in my head but he continues to make me jealous….
But I didn’t contact him until the last September I request him on linkdin, he didn’t answer but his friends (all) look at my profile
I always have the feeling that he still loves me ,but at the same time I resent him for broking my heart … Why does all of his friends and girls knew all about me, why he did not accept my invitation? why it really bothers me….Maybe he actually moved on….