Why do I feel like this

On my birthday (21) I was raped by a friend. I didnt talk to him for months after. Not until he messaged me if I remember what happened. (I was drinking) I should have either ignored him or blocked him. But my dumbass decided to say yes. He the proceeded to ask if thats what I wanted to do.. Like if I planned on having sex I said no. He then said well I knew I wanted to. He then asked other question to which pushed my limits on talked to my rapist. I told him he was being disrespectful he asked why I said I had a man. He then asked why was it dont disrespectful before then. I was just beyond baffled. So I called him. My mind was going a million miles. My first thought was OMG what if he tells my fiancé I cheated. What if he somehow manipulates the man I love into thinking I cheated and takes him from me. So we talked for hours. He days goodbye. I block him on FB and SC and me quickly messages me asking if I blocked him. So I hurried and blocked him on insta. I was beyond freaked out. I finally had the balls to tell my fiancé 2 to 3 mo ths later. He was upset for me and respected my choice on not reporting him based on the feeling of possibly not being believed in and being told im a liar. Its been 7 months since then. And i still get anxious and nervous and depressed about the what ifs. What if he somehow messages me of my family or my fiancé and convences them I cheated on him. What if he believes it. What if me not saying no loud enough or me not fighting back hard enough counts as cheating. Is that why im anxious? Because I belive I didnt try hard enough? Maybe. But I just want me thinking to hard at night to stop. I wanted him out of my mind. I dont want to think about it anymore.