I remember reading about this book/story on Wikipedia as if it were yesterday, but no matter how hard I try, I can't find it again.
An astronaut is stranded on Mars and almost starves to death. In desperation, she decides to try the teleporter, which is apparently dangerous technology. It works perfectly, and she walks out to a beautiful day on Earth. However, she becomes obsessed with thinking she's an impostor, and that the "real" person was destroyed on Mars. She feels guilty that her children are "motherless" because the teleporter "killed" their real mother on Mars. The rest of the book is about the philosophy of teleportation--are you the same person after teleportation, or a completely different one?
Any help is appreciated. I'm beginning to think this isn't a real story--but that would be very creepy, because it would mean I hallucinated a lot of details that I think I remember clearly.