Abigail Williams is a contradictory figure. She is bright, charismatic and persuasive. Yet Abigail lacks a sense of fairness and morality. She is selfish, vindictive and reckless in her willingness to harm others.
She is at once a frightening and pitiable character, malicious in her accusations and sad in her need for close human contact and attention.
The conflict that Abigail faces is one of personal redemption and emotional need. She wants to recapture the attentions and affections of John Proctor but feels that she has no "good way" to do this. When an opportunity arises for Abigail to accuse Elizabeth Proctor and thereby remove an obstacle in the way of her desires, she does not hesitate or apologize.
Abigail wants, simply, to be loved (by Proctor) but she acts out in an extremely malicious way. This lack of morality and empathy is ironic when we consider her simple and very human aim. She is willing to effectively kill someone in order to be loved.