At the opening of the play, Abigail is in a rather bad position. Without parents to defend or protect her, Abigail relies on her uncle. Parris is not necessarily on her side, however.
Parris warns Abigail that her reputation is already under suspicion as she has been dismissed from the service of Goody Proctor and has not been hired since.
More recently, she has been seen dancing in the woods naked and drinking blood. As Betty pretends to be sick to escape punishment for her role in the revelry in the woods, Abigail realizes that if the girls are truly found out they may be put to death.
Abigail knows that she needs to protect herself she must also deflect attention from Betty and Reverend Parris. For his part, the Reverend's character suggests that he will cast out Abigail before standing by to defend her.
He knows not only that witchcraft is punishable by death, but also that the consequences of such news getting out in the town are dire to his own reputation.
In this scenario, Abigail has nothing and no one to fall back on. She has no social capital and no actual capital. She has no power in the community and she is close to being accused of a serious crime in Salem.
A significant number of her actions across the rest of the play can be seen to have grown out of her desperation and powerlessness in this moment.
Another kind of powerlessness associated with Abigail's character is found in her relationship with John Proctor. She wishes to rekindle their affair, but is powerless to do so. Proctor is now set against any reunion.