Tragic characters generally evoke pity for an audience. In order to determine how much of a tragic character Abigail is, readers and audience members need to ask whether or not Abigail merits sympathy. Does Abigail experience any hardships in the novel? If so, do these hardships and trials excuse her for the harm she brought to others?
Early in the play, the audience finds out that Abigail is an orphan. Her parents were brutally killed by Native Americans. (There were many battles over land happening between the Native Americans and the early European settlers.) Abigail shares the details of her parents' murder with the other girls when she demands that the girls keep quiet about the events that they participated in together in the woods. Abigail says,
Let either of you breathe a word ... about the other things, and I will come to you in the black of some terrible night and I will bring a pointy reckoning ... I saw Indians smash my dear parents’ heads on the pillow next to mine ... I can make you wish you had never seen the sun go down! (Act 1)
Abigail's backstory is extremely unfortunate. Not only is she an orphan, but she supposedly watched her parents being murdered by Native Americans. This would be extremely upsetting to anyone.
Abigail becomes romantically interested in a married man, John Proctor. The two end up having an affair. While affairs are still considered inappropriate in modern society, this inappropriate relationship would have much more serious consequences in a Puritan government. Both Abigail Williams and John Proctor would face extreme shame and severe consequences if their affair was discovered.
In a quick private conversation between the two of them (before the hysteria breaks out), Abigail tells John Proctor that he still loves her. He, however, continues to assert that he will never reach for her again in a romantic way. He asks her to "wipe it out of mind" and to imagine that they "never touched" (act 1).
This leads Abigail to show even more emotion. While crying, she says to John Proctor,
You loved me, John Proctor, and whatever sin it is, you love me yet! ... John, pity me, pity me! (Act 1)
Abigail is upset that John Proctor claims he will not love her anymore. Additionally, she has no parents alive who love her. She is involved in an affair that could get her into very serious trouble if the relationship is discovered. Additionally, she participated in an event in the woods that Puritan judges considered witchcraft. Witchcraft also had severe consequences (sometimes including the death penalty). These are all reasons that the reader might sympathize with Abigail. One could argue that Abigail is, to some degree, a tragic character.
Yet, others will argue that Abigail is unworthy of sympathy. While she experienced real challenges, she brought suffering to others. For example, in act 3 she lies about Mary Warren, saying that Mary Warren is attacking her with witchcraft (in the form of a yellow bird that is unseen by the others). She does this to get Mary Warren in trouble. Mary Warren comes to tell the truth in the courtroom, and Abigail is willing to do anything, even lie about her friend, to stop Mary Warren from telling the truth.
Additionally, as the trial continues, more and more people get accused of witchcraft; if found guilty, these men and women may be killed for witchcraft. Abigail leads the other girls in accusing other townspeople of witchcraft; she refuses to tell the truth about her own participation in witchcraft in the woods (or about her affair with John Proctor). She lies and allows innocent people, including Elizabeth Proctor, to be falsely accused of witchcraft to protect her own reputation. It is assumed that she accuses Elizabeth so that she can marry John Proctor (if Elizabeth is killed).
Before the end of the play, Abigail runs away with a large amount of her uncle's money. She never confesses to participating in witchcraft or to her affair with John Proctor. She allows many innocent people to die. For these reasons, one might argue that Abigail is unworthy of sympathy. Abigail faces real struggles in her life; she also brings harm to many others, with no obvious remorse for her actions. She is not fully a tragic character.