My brother has Asperger's and is 25 years old. He went almost all of his childhood undiagnosed with Asperger's but had various diagnoses such as ADD and hypersensitivity disorder. During college he went into a tailspin of social withdrawal and we removed him from his cockroach infested apartment after dropping out at a weight of just 125 lbs (and 6'). We got more information on Asperger's and my parents agreed to care for him full time if he would talk to a therapist and follow their protocol. This was disagreeable to him and he has been homeless and directionless since.
Me and my parents have tried to care for him by giving him money, offering therapy, connecting him for jobs or just providing encouragement but he has become more and more distant--now refusing all help and almost all contact. He emailed my mom recently and sent her a long, scathing note accusing her of being a terrible parent (pointing fingers at her for feeling sorry for herself during intense cancer treatment) and calling my father the devil. He said that he is on earth for one purpose ('to speak Godly truth') and made it clear he actually believes my father is the devil.
At this point, his only contact to us is through abusive emails--we don't know where he sleeps and he does not have a phone. Could his illness be more than Asperger's or is religious obsession or delusion typical of someone who is intensely affected by it? Anyone with Asperger's have advice on how to help him? My last contact with him was an email I sent that said simply "I love you and want to hear from you, but if I don't, I understand. Know that you are on my mind". He never responded.