why Henry acts this way toward the tattered man?

The tattered man just wants some sense of companionship and someone to talk to him; maybe just to listen. Unfortunately, the man's presence, conversation, and discussion horrify Henry because Henry can't participate in the conversation. He had fled the battle; he had nothing to say, and the man's continued presence made Henry more and more uncomfortable with every passing moment. I think Henry is so stressed and agitated that he was not obliged to talk to the tattered man.