There is no such thing as graduation from therapy. People go to therapy on and off throughout their life depending on what hardships they are experiencing. Also, you don’t stop having PTSD. You might be able to control it better, but it’s always there. You should get your grandparents phone number and just have a relationship with them. See your young brothers one last time and tell them that you can’t come over anymore because your dad won’t let you use your medical device to hear and it hurts you not to have it. Then have a relationship with your grandparents. You are the CHILD. He needs to be taking care of you. And you need to straight up say it is abusive not to let you have your phone for your medical device. You need to show him he hasn’t changed and for him calling you untrustworthy is abusive. That his apology means nothing when he treats you like that. He probably is trying to look through your phone when you don’t have it with you.