The Martian Chronicles - Ray Bradbury

The men of Earth came to Mars. Only a few came at first, for most men felt the great illness in them even before the rocket fired into space. And this disease was called The Loneliness, because when you saw your home town dwindle to the size of your fist and then lemon-size and then pin-size, you felt you had never been born, you were nowhere, nothing familiar, only other strange men.