Why does Paul wish he had never returned home for his leave?

Paul is disillusioned about his trip home. His mother is dying and little will be done to help her. His father parades Paul around the town in his uniform. People think Paul is a hero and that Germany is actually winning the war. Paul says that they no nothing. Paul cannot connect with his past. He has changed since he left his town and grown into someone unrecognizable from his former self. Paul just wants to return to his comrades at the war.