Depression. His mind is not fully gone.

My cousin is going through a tough condition for 4 or 5 years. His parents hide it so we couldn't help him earlier. Whenever we went to his house, he never come out.He will stand at the door, says hi,gives a smile and will go inside. Nobody is allowded to go inside that room. Upto age 25 he was cheerfull and smart. I heard from my other cousinsister that he had an affair that went wrong. His parents says it is not the reason.They says that, he faced a shocking incident from somewhere. One of my uncle and his parents itself scolded him that made the situation worse. Now also my relatives and his parents too,are not taking it seriously and thinks his life is over. His parents tried for treatment and from a hospital they give so many medicines that made him weak and he seems very much depressed now also. No one can take him out of that room because if anybody tries, he makes loud noises, breaks things..He go for bank,psc exams himself, which gives us hope that his mind is not fully gone.