A struggle with understanding

I have recently been engaged with an internal struggle about what has happened to my sister.  The past several years she has become very stressed and more and more forgetful.  Of course all of us struggle with stress and it is the bane of most of us as we get older to struggle to remember names and words which only come to us later.  I for one am quick to substitute words like thingy , thing a ma gig, what's it, that woman, honey or even sqigamahala (my own word for things whose names remain elusive).  Of late or the last year my sister does not recognize the man she lives with as her husband of 60 years.  She knows his name is Gene, but not her Gene.  She will insist  there is a stranger in her house and she will demand from time to time proof that he is really Gene.  When she is shown  papers like Drivers Licence, etc, she will insist anyone could have those made.  Jackie was always a great fan of mystery stories, puzzles and crosswords and she definitely knows of what she speaks regarding fake identification.  Jackie has been diagnosed with Dementia.
When I call her on the phone she seems normal for the most part with an occasional lapse into forgetfulness which really seems to bother her.
For my own understanding I have looked up the differences between dementia and Alzheimer's and the best short description I am quoting below:
 " According to the Alzheimer’s Association, Alzheimer’s Disease is a specific type of dementia caused when high levels of certain proteins inside and outside brain cells make it hard for brain cells to stay healthy and to communicate with each other. This leads to the loss of connections between nerve cells, and eventually to the death of nerve cells and loss of brain tissue.

 "Here's the major  difference between Alzheimer’s Disease and dementia — when an individual is diagnosed with dementia, they are diagnosed based on their symptoms without actually knowing what's behind the symptoms. In Alzheimer’s disease, the exact cause of the symptoms is understood. In addition, Alzheimer's disease is not reversible, whereas some types of dementia, such as those caused by nutritional problems or a drug interaction, can be reversed."                                                                                                                                                                I only wish my sister's disease which has been diagnosed as dementia could be, at least partially,  reversed.  I have had extremely vivid dreams the last 10 years.  They are like stories which can be interrupted and continued.  If I wake in the middle of a dream to go to the toilet, when I return I can go right back into and continue my dream.  The dreams are extremely realistic and most often involve people I know or family members.  There are a large number of themes and they keep recurring.  I will list only a few:  my mom is alive and alone and living is a specially constructed house in upstate NY.  She is divorced from my father, who sometimes has remarried, or is sometimes still married to mom.  Sometimes I have gone to visit my sister, in a sprawling estate which encompasses a lot of acres of woods and mountains.  Sometimes this property is in NY State and sometimes it appears to be in a state like the Carolina's or Tenn.  The actual house is always in disrepair, filled with unknown distant relatives, Jackie has gone out shopping or some kind of cult religious meeting with her daughter.  I am trying to clean the kitchen, find food and deal with various relatives I don't know.   As I mentioned before there are several dozens of themes and settings but they keep recurring and are rich with details and conversations and locations.  They always take different forms regardless of the particular theme and often involve arguments and conversations with relatives I have experienced problems with. I am always fascinated with these stories in my dreams and I want to go back into them to see how they come out or what is going to happen next.  They are extremely clear when I am in them but when I try to explain a dream to others I can only remember a few details and they are confusing.  When I was speaking to my Nephew the other day and he was explaining what Jackie sometimes experiences as her reality, I was struck by the similarity to my dreams.                                                                                                                        It occurred to me that it sounded like she was experiencing some sort of a dream or fugue state.  She recognizes the characters in her state but their reality is different.  She sees as if through a fog or dream and her people are sometimes who they really are and are sometimes very different from the persons she has known and loved.  This can be in the same waking time frame.  she will recognize, remember and talk to Kenny or Debbie and yet not recognizer Gene.   Even when they are sitting and eating at the same dinner table.  Gene is a nice man but simply not the Gene she was married to for 60 years.                                                                                                                  In my dreams the people are not the same ones I know in my waking life either.  They are either much nicer or nastier and appear in different settings than I have ever experienced waking.  Can this be somewhat like string theory or parallel lines which never meet, but in reality do meet???????
  I guess this is my theory to integrate reality, fugue states and dementia, a tapestry. 

     What is string theory in 10 words or less, by bgreene"It's an attempt to unify all matter and all forces into one mathematical tapestry."