I think people are in such shock that they don't realise that what they say really hurts the person concerned. When I rang my mother to tell her that I had breast cancer, her answer......."I knew, I just knew you had breast cancer". I was dumfounded, I couldn't believe what she had just said. I never answered her back because "I wouldn't be that rude!" It's like when people constantly tell you to "be positive", they don't know what you're feeling, you try to be positive but sometimes it's just not that easy.
Good luck with your operation and we'll be thinking of you.
Dale xx