Am I extra sorry long post

so today me and my now ex boyfriend and I where together today he came over and we watch power and was talking I went to give my son his medicine and make a bottle for him and when I came back he asked me who was Sean. Sean is a my son dad ex best friend but he still checks on me and make sure me the baby doesn’t need anything because he’s like a older brother to me I knew him first before I meet my sons dad. Mind you Sean and me never was like that wanna be in a relationship even before I met my son father. So basically Sean texted me and asked me what I was doing and I said chilling with my son and boyfriend. When I went to get the bottle and give my son his medicine he (my now ex boyfriend) gonna make it seem like I was cheating. Like he wants me to cheat mind you. This is not the first time he did it he went through my email before and even went though my spam mail. Like am I the extra one or is he cause I told him to leave and don’t come back because. Doesn’t want me to have male friends if he doesn’t know them. He’s the one being extra and insecure. It’s like he doesn’t trust me and I didn’t never give him a reason not to trust me. Was I wrong for telling him to leave and don’t come back?