Hi I'm new here. First a little foreshadowing. I've always been an avid reader. After returning from the Vietnam War I found myself reading a lot of SF (I wonder why?). I read many classic's in the 70's. There is one book that particularly connected with my state of mind. I don't remember the title nor the author. I read it between 72-77. I believe the story revolved around a pair of astronauts sent on a mission to a distant planet. Slowly the isolation of outer and inner space drives the astronaut/s mad. I don't remember any more details, but the story spoke perfectly to my own experience of war induced isolation, stress, and madness. It took me a long time to realize my inner/outer experience was normal given the circumstances. Well, any help in finding the book would be greatly appreciated. Thanks!