Hi am Asking this for my MIL. She is 59 years old and she is physically very healthy. Also she is the caregiver of my father in law who is completely blind. My concern is about her mental health. Her Behaviour has changed completely over the last 4-5 years( Which I heard from the family members I only knw her personally for a yr after my marriage) but currently she is very aggressive towards my blind father-in-law. And she is not able to follow any normal instructions it will take alot of repeating to get her to understand something. And if we instruct her to do something she cant actually follow it at all. i have noticed she is having difficulty in proces new info and her memory seems ok. I have often seen her just repeating wat just she heard and she just sings random thoughts.she have difficult in deciding something.  she is obsessed with going out but she wont go alone. it's very hard to have a normal conversation with her .is this dementia? please advise.