Dude, I was lying in bed and I turned around and There was my birth mom lying next to me and I asked her a question and she replied. Im sorry to hear about your friends. I think what you need is closure. Some kind of closure. Do you go to his gave site? Or is that too hard for you? Cause if it is then you could write him a letter and put it in your room. I wrote my birth mom a letter and she stoped scaring me at night. popping up next to me in the middle of the night. giving me visions. you could do something related to him. that shows your brain that he is no longer there. like when he doesnt show up for something. when you expect him to. it'll let you down. then it might stop. these are suggestions. just find ways to trick your brain.