Best friend

I have a question so 13 years ago I met this guy and we became best friends but I also fell in love with him. He never felt the same way about me, I tried getting over him and I did. Then I met another guy. My best friend and I still talked occasionally but I wasn't in love with him anymore. I am happy with the guy I am with now. We are engaged and we are together for almost 8 years. But the last few months I have been thinking a lot about my best friend and almost constantly dreaming about him. I miss him talking to me he stopped talking to me about 4 years ago and I don't know what I did wrong and I don't want to confront him about it because I am scared he is going to think it's weird. Is it normal that I feel this way now? It's kind of driving me crazy