What quotes from "Soldier's Home" show that Harold has been mentally and/or physically separated from society?
At the beginning of the story, Krebs's disconnection from society is made evident when the narrator observes "he came back much too late" from the war. The welcome ceremonies for the returning soldiers had come and gone, and Krebs receives no acknowledgment of his service.
Krebs shows minimal interest in rejoining society. His days are characterized by a great deal of solitude as he "was sleeping late in bed, getting up to walk down town to the library to get a book, eating lunch at home, reading on the front porch until he became bored" and then sometimes playing a bit of pool in the evenings. Though Krebs finds the girls in town attractive and longs to make a connection, he concludes that "he did not want them themselves really. They were too complicated." Krebs lacks the mental energy that would be required to develop relationships. He decides that "he did not want to have to do any courting."
In the town where Krebs lives, people have moved on from the war, but he is unable to; he finds that people aren't interested in talking about it, and so "he sat there on the porch reading a book on the war. It was a history and he was reading about all the engagements he had been in. It was the most interesting reading he had ever done." Krebs is stuck in his recent past and can't communicate his needs to anyone who hasn't shared his experience as a soldier or who lacks the understanding of how it has changed him irrevocably.
Four paragraphs into the story, Hemingway reveals Harold's isolation upon returning from the war by telling us,
"At first Krebs...did not want to talk about the war at all. Later he felt the need to talk but no one wanted to hear about it".
Krebs thinks about going out with some of the girls he used to know, and remembers girls he knew overseas, but finds,
"...the young girls had grown up...they lived in such a complicated world of already defined alliances...that (he) did not feel the energy or the courage to break into it".
"He wanted to live along without consequences".
"...the world they were in was not the world he was in".
"You did not need a girl unless you thought about them. He learned that in the Army".
When Krebs' mother urges him to find work, saying,
"There can be no idle hands in His Kingdom",
"I'm not in His Kingdom".
Finally, after the emotional scene when he tells his mother,
"I don't love anybody",
Krebs realizes that despite all his mother's pleadings and the lies he had to tell,
"...none of it had touched him".