There are two types, "wet" and "dry." There are treatments that can slow both, although if she's in the earliest stages, she might not need them quite yet. Still, the doc should have spent a whopping 10 minutes to talk to her about them.
She can't do anything about genetics, but if she smokes, she needs to stop now. Smoking doubles the risk of ARMD. There is a small body of research that says a diet high in (guess what) dark green leafy veg, fruits and fish can slow the disease. Antioxidant vitamins, probably what the doc gave her, can also slow the disease but not by much.
My mother went blind with ARMD before they knew much about it. There have been no other cases on that side of the family, so I'm blaming her heavy smoking history for it and hoping for the best. I had a coworker with Stargardt's disease, a very early form of the disease, whose vision was compensated by some very weird looking glasses that looked like little telescopes. His aided vision was good enough for him to work as a pharmacist in a big hospital, although he couldn't drive.
So there are options. A good doctor will discuss them all with her, so tell her to go find one.
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