The last paragraph of Hawthorne's "Young Goodman Brown" helps to answer the question if the story actually took place or if it was just a dream that Brown had. The sentence preceding the final paragraph asks that exact question, in fact; but whether it was a dream or a real-life experience the rest of his life would never be the same. He didn't look at the preacher, his wife, or anyone else in town the same again and died a bitter old man. He didn't even regard his children or grand-children with much more respect than he did others because his trust of other people being what they seem was gone afterwards. he never recovered from seeing people that he thought were pure and innocent actually have hidden secrets of sin even though he himself was on the same path of temptation (What a hypocrite, huh?). His bitterness, self-righteousness, and pride held him back from forgiving others, accepting people for who they are, and living a life of happiness. Acting like that doesn't score any friends because, "they carved no hopeful verse upon his tombstone, for his dying hour was gloom".
I have never seen Goodman Brown as a hypocrite. I think his inability to "forgive" was based on the dishonesty of the community. The fact is they presented themselves as one thing in the light of day. Ministers preaching to children about sin when they themselves were sinning! Goodman Brown looked around and felt isolation and despair. Even if the experience was a dream, it clearly indicates that he had a deep-seated distrust of the others. Perhaps he sensed their dishonesty. No one owned up to behaviors but rather just went about their business. They were the hypocrites in my opinion and GB had no one to turn to. He didn't even trust God at that point which is the real tragedy.