How does Hawthorne describe the contrast between how Hester and Dimmesdale think about their ability to leave town?

Hester has always been more passionate about breaking free than Dimmesdale. Her ability to leave Boston is in line with her stubborn perseverance not to let the people in the village destroy her. Dimmesdale is much more cautious. He is shackled to both the village and Puritan ideology. In chapter 18, he allows himself to share in Hester's passion which seems to take the weight of the world off his shoulders.