he ghosted me ...

Hi so me and this guy had a thing during the summer which was just hooking up. we ended because he told me he was still in love w his ex. and he was lowkey a rebound because I still had feelings for my ex but anyways we decided to leave on good terms and friends however he did not keep that. He ghosted me shortly after which I feel bad because I want to be friends with him, I texted him and got left on read and then I got mad and unfollowed him and he unfollowed me as well. Why do guys act this way? All I want to do is have my friend back...So what can I do to get over it? And just be okay with the fact that I may never have his friendship again? Also we’re in the same friend group so I know it was mistake sleeping with him but there were no feelings!! and it’s his birthday and my friends and him are planning to do something but he uninvited me, so now I feel very upset. please help, how do I get my friend back? Or how do I move on? Thank you!