Elizabeth accuses her husband of cheating on her with Abigail.
John Proctor seems to have had an affair with the servant girl, Abigail. He considers his wife cold and hard because she accused him of this, and because ever since then she has been treating him distantly.
You forget nothin’ and forgive nothin’. … I have gone tiptoe in this house all seven month since she is gone. I have not moved from there to there without I think to please you, and still an everlasting funeral marches round your heart. (Act Two)
In his mind, he made a mistake and they need to move on. He tells her that she needs to “learn charity,” as if it is her fault. She sends Abigail away, and that should be the end of it. But it is not the end of it for her. To her, things are serious. She still feels betrayed. She has that memory whenever she sees her husband.
Unfortunately, the incident is not just their internal pain. When the witch trials begin, Abigail is front and center. Elizabeth makes the choice to testify that there was no affair between her husband and the servant. She thinks that she is protecting herself, and her family. Unfortunately, what she is doing is dooming her husband. Things have gotten so far out of control that there is no way she could have seen it coming. People can easily accuse anyone of witchcraft and consorting with the devil—even if they are innocent, even if it is obviously a way of getting revenge. This is just what Abigail does.
Abigail accuses Elizabeth of witchcraft, even though she was the one dancing in the woods. She hopes that by getting Elizabeth out of the way, she can marry John Proctor. Her self-serving accusations, and Elizabeth’s testimony, lead to John’s sacrifice to try to right his wrong.