How do Proctor's feelings toward Abby change in "The Crucible"?

I the play "The Crucible" John Procter had been involved in an affair with Abigail.  He realizes he was wrong and tells her that he has to end the relationship.  He did not want to hurt her in the beginning but was aware that his actions were wrong.

After Abigail starts going against  John's wife and falsely accusing her of witchcraft, John is aware that she still wants him or to hurt his wife.  Abigail makes some derogatory comments to John about his wife.  John pleads with her to drop the charges.

As John sees more evidence of Abigail's willingness to allow his wife to die for her own selfishness, he becomes angry and enraged with ehr.