Sometimes you can make a difference... sometimes it won't matter what you do. I would try to offer some sort of comfort, (since I have no tangible advice) but all that comes to mind are literary quotes that seem... not enough right now.

Do what you can, keep fighting, thank your wife for her support, but... remember... come what may. You have lived through it before, you can do it again.

However, what seems to be your true concern is what awaits you on the other side... it only matters if you don't think you can fix anything what might break. I wouldn't worry about those "things" that haven't happened yet. There will be time enough for that later. Focus on what is in front of you. That is what you can effect.