How does Young Goodman Brown’s new understanding, maybe from having dreamed it, going to make him into a better person in the future?

Goodman Brown is unsure whether the experience of the occult forest ceremony was real or simply a dream. Regardless, he returns to Salem a changed man, doubtful of everyone else's piety. In short, he has lost his faith in mankind, perhaps even in himself; his religious faith has certainly been shaken, and he dies a lonely, bitter, and gloomy man.