There's certainly a lot we could share with you from our own experiences, and I'm trying to think of what to share and how to share it so it won't be as overwhelming. I guess one way is just to let you know to feel free to send an e-mail my way if you have a question about something or just to inquire about our experiences whenever you're wondering; we're more than willing to answer.
It boils down to 3 categories: the things that we've been doing right, the things we would have started sooner, the things we would have done differently because we have come to realize that they didn't work and were a waste of time and energy (and sometimes money, too).
Continue to stay a part of her life as much as possible. Even if the day comes that she doesn't recognize where you are in life (i.e. thinking of you in your younger years), it doesn't mean that it'll be like that from then on, but just that she's thinking like that for the moment. For example, the relatives who visit regularily are the familiar faces that still make my grandma light up, as opposed to those who don't see her very often and now she doesn't recognize them well or at all.
Lots of times the listener's focus can also be that she has forgotten that she already mentioned/asked/etc. something. While that may be so, at least she is remembering that it was important to her and she wanted to share it with you!
A simpler way to look at it is to just answer her as if it were the first time she brought it up. It will be a help to you when it isn't the monotony that is in the focus.
Something that's helped us is to keep in mind that some of the things that happen is "just the disease". I don't want to sound like anything and everything she does has to do with the disease or that it's to blame for everything. But Alzheimer's does cloud the judgment. Sometimes it's just that she would have kept something to herself rather than saying it to our face. Don't take mood swings personally.
I did ask my parents if there were things they would have done differently at the beginning. The above is just a little bit of some of our thoughts, and I will still get back to you with a more direct answer. Right now, I'm just trying to get it down on pen and paper (or keyboard and notepad as the case may be), mostly just trying to find the words that best express what they've said.