Ive had experience...
My Mums mother had liver cancer, which spread everywhere, she died sadly but she was over 70, so not bad!
My mum had ovarian cancer, she has a massive hysterectomy and that cleared it up. They got it early.
My Uncle on my dads side had pancreatic cancer. They are treating that now, he is still alive.
My Uncle's son has prostrate cancer. That was fixed easily and hasnt come back.
So all in all i worked out im 80% to get it myself! Figured upon hearing that id smoke more and make it 100% as I dont like getting sucked out on
As for advice, if its a double masectomy, depending on the treatment your hair should be ok. Unless you end up with chemo then in which car plugs, extensions, or just a nice hat work. And you never know, i found a bald woman hot once!!
For foods, fish is meant to be good, omega oils, vitamins, that kinda crap. All i know is that i got told to stay off carbonated drinks. Dunno if that is true or not. If you smoke, stop! If you drink, also stop (at least for now)
As for your husband, the only advice is to get ready for a lot of extra work looking after the house and you.
Thats all i got