The best revenge against a sociopath may be simple avoidance, since by definition and by their nature, a sociopath has no conscience, takes pleasure in manipulating and hurting others and feels no remorse about their actions. Getting away from their web of deceit and manipulation is not only revenge, but a defense.
A sociopath often seeks out empathetic personalities precisely because they will respond to emotional manipulation best. The first step in dealing with such a personality is to identify the sociopath's dysfunctional behavior. If it is not possible to fully dissociate from the person, then minimizing contact is the next best solution.