Chapter 14 - Hester and the Physician
This unhappy person had effected such a transformation by devoting himself, for seven years, to the constant analysis of a heart full of torture, and deriving his enjoyment thence, ......
It seems obvious at this point that Chillingworth is seeking revenge on Dimmesdale for what has happened, although he has forgiven Hester. Along with revenge, Chillingworth also seems to take great satisfaction in Dimmesdale's tormented life. This seems to be a fate worse than death for Dimmesdale, as Hester states, "Better he had died at once!"
"Woman, I could well-nigh pity thee," said Roger Chillingworth, unable to restrain a thrill of admiration too, for there was a quality almost majestic in the despair which she expressed.
These lines here speak to me that there is not so much forgiveness, as there is a heightened exhilaration to Chillingworth's madness about the disruption he is causing poor Hester.
Where exactly do you see proof that Chillingworth has forgiven Hester? From my point of view, it would appear more so that he is loathing her even deeper. Take a look at their discussion in the woods in Chapter 14. Half of the time, Chillingworth is taunting Hester for her past sin. A great example of this taunting could be see in the following passage:
" "It was myself," cried Hester, shuddering. "It was I, not less than he. Why hast thou not avenged thyself on me?"
"I have left thee to the scarlet letter," replied Roger Chillingworth. "If that has not avenged me, I can do no more!" "
Chillingworth doesn't so much forgive Hester as he does take all of his frustration out on Dimmesdale. Hester is already suffering, like Lexi said, from the scarlet letter. But if Chillingworth were to succeed in damaging or killing Dimmesdale, wouldn't that count as a "double header?" He'd have killed the father of his illegitimate child and he's have additional revenge on Hester, as she would watch the father of her child pass away.
So with this in mind, he hasn't forgiven her, because his final objective spills over far enough to hurt Hester.
I believe Chillingworth's forgiveness of Hester is in his response to her "I have left thee to the scarlet letter." He knows that was punishment enough for her sin and may even pity her. He even goes further to say that "...hadst thou met earlier with a better love than mine, this evil had not been. I pity thee, for the good that has been wasted." His obsession is on tormenting Dimmesdale and watching him suffer for what he has done. All of this wasted energy is what turned Chillingworth from a "kind, true, just man to a fiend who does the devil's work."