Reminiscencing my teacher...!!!

I still remember my History teacher who was very famous for her magnificent memory as historians are illustrious for their good memory. She taught me from class 6th to class 12th. (In India we call it intermediate) but soon she was retired and after 3 years we went to meet her at her residence. . She welcomed us and discussed all about our future plans and the past reminiscences but in between she forgets the whole thing and in between she just ask who are you all. To whom do u want to meet? We were shocked with this impulsive activities.other than again after 10 minutes she started asking about the Modern History .We were very sad that day. I always heard about the people who are exaggerated with this situation. Is it Alzheimer’s or Dementia? Or Schizophrenia? Are there any scientific definitions for this situation? Despite the fact that in many movies and fiction we have read and seen this character but when it comes to a real life it is an unforgettable…I was apprehensive about my teacher but seems her situation could not be back to a normal life. She lives all alone in her big house. She lost her only son in an accident .No body could guess the actual reason for her coming and going memory. She was known as the one who can’t forget any date any name any event. Whenever I am in my home town I stop by and meet her, in this hope that she will recognize me at least for one minute only and I will live that moment and rest of the time I sadly look to what she does all the time. Though no body has the right to peep in other’s personal life but as the matter of sentiments I want each of her details to be written where I can state what is the pain of that and what a person is with her memory and what she is ,when memory is not with her. What could be called… a tragedy where she feels it each and every second.