Hawthorne creates the conflict between Dimmesdale and society as an example of a character who surrenders their individuality to the community. Unlike Hester, Dimmesdale conforms to fit societys expectations as a sinless reverend. He has successfully kept his thoughts and feelings locked inside his heart. His inability to embrace the guilt is the source for his sick ness, and each day it worsens. His hidden and unspoken sin continuously tears apart his physical and mental health. It is not until the very end of the book does Dimmesdale finally confesses his sin after preaching his last sermon. Because Dimmesdale was unwilling, or unable to fight for himself, he was left in a position of powerlessness, he embraced his spirituality and delivered compelling sermons. While thus suffering under bodily disease, and gnawed and tortured by some black trouble of the soul, and given over to the machinations of his deadliest enemy, the Reverend Mr. Dimmesdale had achieved a brilliant popularity in his sacred office. He won it, indeed, in great part, by his sorrows. His intellectual gifts, his moral perceptions, his power of experiencing and communicating emotion, were kept in a state of preternatural activity(page 94) His ability to preach on the topic of sin was enhanced because of his suffering.
Chillingsworth has committed the worse form of sin. His heart has become darkness, so the only making others suffer- does he feel satisfied. His physical being deteriorates with each passing day as he becomes more evil, and loses his human qualities. Hester didnt disclose his identity earlier because she didnt fully comprehend exactly how evil Chillingsworth has become, and how much pain hes caused Dimmesdale. Now that it is clear, Dimmesdales suffering has been brought upon by Chillingsworth, Hester feels that its her responsibility to warn Dimmesdale of Chillingsworths evil plans.
I think its fair for both Hester and Dimmesdale to pity each other after what they have been through. Both characters went through a relationship that was completely unaccepted by society- Hester was forced to reveal her secret- and be isolated in society, while Dimmesdale was forced to hide his- with the haunting feeling of guilt. Both characters felt the same pain, if anything Dimmesdale felt more pain. Its possible that the author is showing how simply revealing your sins, will hurt less than keeping them bundled inside. In the end I feel more pity for Dimmesdale because his entire life was crushed by this scandal- and he lacks the will power to get himself out.