They may begin to question and doubt their perception and knowledge, or they may start to defend their experiences by proving and justifying themselves. Defending, proving and justifying are generally associated with the emotions of anger, resentment, frustration and bitterness. When a person is defending themselves, the other is perceived as being in opposition - a threat. The perceived threat can be met with distancing, by establishing boundaries as a form of protection from denial or rejection. Consequently, trust, intimacy and sharing can be lost through the fear of rejection.
Anger is very much a part of relations of denial, in fact anger is mutual denial.
In most situations anger triggers anger, reinforcing mutual denial. Understanding cannot be reached through mutual denial as both participants protect by distancing themselves through establishing boundaries, thus generating and maintaining a lose, lose situation. This pattern will become familiar if a person participates regularly in relations of denial. Depression, isolation, loneliness and abandonment flourish as low self esteem deepens and rejection intensifies. When the individual's insecurities are triggered, they may respond in anger as a means to protect against rejection.