Anyone know the name of this book?

I read a book my senior year of high school (back in 2003) that I remember really liking a lot. I could have sworn it was called 'The Beach' or 'Beach' but I can't find it on amazon.com so that's probably not it. I'm kind of at a loss since amazon.com has never failed me. It was set in the near future but there was no specific date, in Australia. A nuclear war had broken out and the world is in chaos. I think, but I'm not certain, that Austrailia was the last to be hit. It was centered around a couple who had just had a baby coping with their friends, neighbors, and family members getting sick and dying around them. There was an expedition to one of the other countries that had already been wiped out. The book ended with at least the wife dying (the child had died in the course of the book) and I think the husband was still alive when the book ended. Sorry I just gave away the ending I'm trying to give as much details as I can remember. If you know the book I'm talking about can you tell me what it is and where I can get it from? Thanks!