Dualism essentially involves two personalities. When you attain God realization you experience His divine happiness everywhere. Before that you are aware what you perceive.
Philosophically speaking no can induce sufferings to anyone else. Sufferings are due to you because of your past deeds, other persons just carry them to you. If you were innocent you would never get exposed to such situations. God determines your exposure.
Sometimes it is essential to prove someone wrong if his or her ways are harmful to himself or herself. It is not a display of adverse attitude towards individual but it is an act, which could bring some relief to the individual.