38 and forgetting / substituting words / memory concerns

my wife started showing signs of dementia at 38,diagnosed at 40,but she has extreme lichen planus,immune system problems and brittle skin(lack of zinc),stress is a funny thing,it causes no end of problems,have you ever heard of carers dementia,you feel you've got dementia because you're so stressed,why don't you find a mmse test on line to put your mind at rest.