If you go on www.alz.org, you can surf through some of the areas and find stages of Alzheimer's or just google "stages of Alzheimer's" and you will find information.
I was SO much like you, actually made myself nuts, reading for hours and hours on the topic, trying to figure out where my mom was, and where she was going. I have come to realize that NO ONE can really tell you exactly the stage, or what is to come. Alz hits every single person differently. Yes, there are some similarities but bottom line, everyone's journey is really different.
I have a friend who cared for her MIL who had Alz and she was able to talk until the very end and in fact recognized my friend and her husband and called them by name, yet, if you read about the stages, it will tell you that at end stage, they are incapable of talking.
There is a book "The 36 Hour Day" which I found to be very valuable, so much information and will probably help you through a lot of your questions. I would strongly recommend, though, that you not take that information as gospel. As I said, I drove myself nuts watching my mom, observing, trying to figure things out. The best advice I can give you is try to enjoy the moments with her and continue to let her know how much you love her...