Which Alzheimer's symptoms get worse over time?

About 4 years ago my mother-in-law got lost coming home from my sister-in-laws house (less than 5 minutes away from her home). We then took away her keys. She had lived alone. Then she started to forget taking her meds. She then forgot to eat. She broke her leg, had surgery, and her memory became awful. My mother-in-law now lives with us. She has been living with us for the past 19 months. She can remember what is said to her, and then about 2 minutes later she'll ask the same questions again. She forgets where she is (our home) but remembers where the bathroom is. At times she forgets where she sits at the kitchen table every afternoon/night. She remembers her chair in the living room "most" times. She forgets she has a bedroom until she gets in it and then she says "oh" this is my nice bedroom. She does not know any other rooms in the house. If we put her in another room she would not know how to leave it. She occasionally recalls that she goes to my sister-in-laws on week-ends. When she is at my sister-in-laws she forgets that she lives with us. When she comes back from my sister-in-law on Mondays she is very, very confused. She is aware she is "extra" confused and gets sad and says "how did I get like this"? We have created a memory board for her that gives her answers to all the questions she repeat the most, like "why am I here", "do I have any clothing", etc? She remembers she is 83 years old "most of the time". She remembers the name of the company she worked at but nothing about her job, just that she "thinks it was important." We put a double disposable underwear on her at night, and she wets through them once in a while. She soils also once in a while. She look great, and the doctors all say she is doing well health wise. She is on blood thinners and two forms of medication for her memory. She also takes multi vitimins and blood pressure medication. She does not remember anyone other than my husband and his sister. She sometimes forgets who I am but says "I love to hear your voice when you come in the room". She has once or twice thought my husband was her brother. She does not remember anything about her husband (died) or anyone else in her family, or anything she has done in life (up to 2 min. ago). She is not mean. She is happy most times, excepts when she comes back from my sister-in-law she seems more confused and says, maybe God should just take me. We have several dogs which she just loves (five small dogs that sit on her lap,and next to her on her chair. She does know how many there are, nor any of their names. She has had swallowing problems off and on even when she did not have memory issues, so we make sure her food is soft (not mashed). If you lay out her clothing she can put them on, but you have to be there or she'll forget an item, or gets a bit confused. She was was able to remember things last year before we had to repeat the answer 5 minutes later (it's down to 2 minutes now). It isn't that she does remembers any less, only that the time in between the time you tell her, and the time she asks again is shorter. My husband is the primary caregiver. I meet her needs after I come home from work. I share talks, and TV watching in the evenings with her, answering all her questions along the way, and then I put her to bed. What stage do you think she is in? What signs manifest themselves as she gets worse? Do you know the "average" cost of a health aide (hourly)to provide services in the home in NY are? Appreciate your time. Thank you