Secret friend

i used to hear voices telling me to do things thats all sorted now i got diagnosed with dreppression, i have been on the medication for 2 years now and i was fine, untill about novemeber this year. i started to see one of my mates that had passed away and we would often talk, then he vansished and about a week later i started seeing this other person more and more as days went on we got on really well, his name is drew, we are like friends he tells me hes my little secret the thing is i no no one else can see him becasue when i used to talk out loud to him people would ask me who i was talking to i would ask them can yuo not see him. he doesnt like me talking about him, if i do then he hruts me mentally and physically, i tried to tell some one but he just hurts me, he gets me to repeat im safe im safe when he is hurting me. i cant take it no more its got to bad and im really scared something worse will happen to me, how do i tell them without getting hurt?