Actually, there is a big difference between grade III and stage III. Mine was a stage IIA (2.5 cm tumor, negative nodes), but had my nodes been +, that would have been a stage IIB. I believe stage III refers to the size of the tumor too, and it may have to do with spread to the nodes beyond the axillary, but I can't remember.
Grade III is what mine was too, although a Stage IIA. Stage refers to the size and spread of the cancer. Grade refers to the traits of the cells of the tumor. Grade III is worse than II and Grade I is better....Grade III means the cells were rapidly dividing and poorly differentiated....meaning they had mutated more and looked less like normal cells, and it can mean they are more aggressive cells.
As for her future, yes, she had a good chance to be cured and never face it head on again. What makes it chronic, in that case, is the never knowing if we are cured.....With positive nodes, she does face a realistic chance of recurrance. The thing is that the stats can tell you the liklihood of recurrance or remaining cancer free...but the stats are just stats, nothing is for sure.
Even if she never has to deal with cancer again, her life is changed forever, and she may always look over her shoulder with fear, with anxiety or with power and control. No telling how she'll react, how she'll feel or how her health will be....that is what makes the journey. Be there for her and support her, there are a lot of ups and downs along the road. Just because the physical scars may heal, the emotional ones are still there.
But...there is every reason to believe and hope that she'll live a long and healthy and normal life. Focus on the positive and the future. Yes, there is a chance she can go on and live normally till a ripe old age!