People form relationships and partnerships based on mutual trust. Friendships rely on the trust that you'll both be there for each other. Marriages often end when trust is betrayed. Business relationships and even the relationships between nations rely heavily on trust. When trust is betrayed, people experience anger, pain, and some turn to revenge.
Confidence Betrayal
From early childhood we share our secrets with our closest friends. People rely on each other to voice their most secret thoughts and feelings. Trust between friends is necessary to maintain the relationship. When one partner betrays the other's confidence by sharing information that was intended to be secret, the relationship may suffer. Gossip is another form of confidence betrayal; talking about a friend or partner negatively behind their back may lead to a separation.
Lying and Withholding the Truth
Information is power. When people share information with each other, other people rely on it to be true. Business decisions are made, and relationships are founded on the facts that each member shares. Whether driven to it because of an avoidance of a fight, or because of intentional malice, lying is another form of betrayal. Hiding facts that you know your partner would want to know is withholding the truth, which can be considered just as bad as lying.
Sexual Betrayal
Intimate relationships are founded on the principle that each partner is exclusive to the other, unless otherwise agreed upon. This not only is an emotional commitment, but also is a physical one. Sexually transmitted diseases, including HIV, are a danger to anyone having unprotected sex. If one partner is having a sexual relationship with a third partner, his primary partner's health is at risk. Additionally, women who cheat on their partner may become pregnant with another person's child, and men who cheat on their partner may father a child on the third person.
Treason
Treason is the act of betraying your government or association. When rebels form a coup against a government, it is treason. Turning against your country's leader is treason often punishable by death. Treason against your military leader can lead to death in some countries, prison time and dishonorable discharge in others. In businesses, forming a plot with others to push out a manager, or to advance over them, is treason. Treason is a betrayal taken very seriously.