The thing is, OP, is that Jane's "battle" with cancer is damn joke and offensive to people who actually struggle with it. She wants to battle cancer on her own, given no special treatment whether it be magic or advanced super-science, and on paper I can somewhat respect that. However the problem lies with her contradictory actions and wanting to be "Thor". Mjolnir completely wipes clean any treatment shes given, chemotherapy or whatever, each time she transforms. So no, she's not battling cancer, shes wants it both ways, being a superhero while throwing the cancer card in everyones face. She should either give up Mjolnir to battle cancer the way a normal person would like she originally stated, or drop the hang-ups, get a magic cure, and just be a superhero. All of this is just pointless drama of her own making. Moreover, Marvel can't help but overcompensate how strong and empowering Jane to the point of giving her the ability to wield 2 Mjolnirs, and forcing the original Thor to get a new hammer entirely.