fungus on lungs

She has a fungus in her lungs? Do they know where she got it?

Without more information about her condition, all I can tell you is what information I know about fungal infections in the lungs. Sometimes they can cause Pneumonia that can be somewhat persistent, but can be treated with a long course of anti-fungal medications. It depends on what type of fungus she has. Do they know? Blastomycosis is pretty rare (from what I've read) and unless the doctor specifically says that it is the type she has, you can't assume that it is.

Unless they specifically say that she has cancer, I wouldn't jump to that conclusion, either.

You said she "was" on medication to kill the fungus. Is she no longer on it? How long was she on it for? Is she being treated by a lung specialist? Has she been hospitalized?