82 year old grandmother goes in for surgery tomorrow morning.

I am new to this site, I have been looking for some advice. My grandmother is 82 years old. She has been diagnosed with (early) stage 4 breast cancer. Early meaning they have been able to contain it in one breast, where 3 months ago it started moving into her lungs. They gave her medication to reduce the spot that was forming in her lung. With alot of prayers and good faith, the spot shrunk and disappeared. Now, she is going in for a masetcamy tomorrow morning. Her breathing compacity is only at 50%. And the oncologist is hesitant, saying that he fears that she will not come off life support after the surgery. Even though they fear that, all doctors (sense we got 4 different opinions) agree that the surgery is best, with out it, the cancer is life threatening. The surgery will not be followed up with any Chemo or radiation treatment. She is a smoker and has COPD and NEVER wears her oxygen unless she is sleeping at night (sense she smokes). I am scared to lose her tomorrow. I know I have to put a smile on and tell her that we will pull through this together. I don't know how to support my husband as this is his grandmother. (we lived with them while his grandfather went through Alzheimer's). I have grown verry close with them, so I do consider her my family. However, my husband is not one to show emotion or feel the need to have to be supported by someone else. How do I help my family in this time of need, especially if something does go for the worst. I don't even know how I can be there for myself. And I know that sounds selfish. This is the first time I have had a family member go through something like this. So all these emotions, and everying, are new and I don't know how to handle it. I don't know what to expect, right now I am just hoping for the best! Please if you have any input , feel free to share. And if you can say a prayer, that is even better. Thanks