You've always disliked a particular coworker who strikes you as dishonest, but he is nice to you and does you favors, so you become friendly with him despite your misgivings. one day you learn that he stole personal items from your desk. you now decide to discontinue the friendship. your negative attitude toward this coworker is strengthened through

reduction of cognitive dissonance                      

Explanation:

              Cognitive dissonance in the world of psychology means when an individual have more than one contradictory and different views, beliefs  or thoughts for a person or when he participates in any activity which is against the beliefs and for that he experiences psychological stress.

              It is a situation having conflicting behaviors and beliefs. And this leads to mental discomfort in a person's  mind.

              In the context, I am having conflicting views of my coworker because of his behavior and actions. Sometime she is very nice to me and sometime she steals my personal belongings from my work desk. So I am facing cognitive dissonance towards my coworker. My negative attitude towards him can be strengthen by the reduction in cognitive dissonance.