I liked this one, though I'd have preferred a teensy bit more room for me to believe in the magic of it. There's very little room to interpret this story as being about a real superheroine; with all apologies to ElectricPaladin, nothing at all occurs that requires any other explanation than cancer and a light-hearted excuse for her physical ailments. Honestly, the only thing that makes me at all willing to even try and believe in the magic is the fact that this story is on Podcastle and not Pseudopod, where it would pretty clearly be just a story of grief-induced hallucinations.
Still, an interesting story. Reminds me a bit of "Everything Is Better with Zombies," from Psuedopod (except I think that story pulled off a more viable alternate interpretation option, and was generally a lot more subtle about inserting the dark glimpses of reality in the corners and shadowed places in the story.)