Long-term stress can lead to a variety of serious mental illnesses. Depression, an extreme feeling of sadness and hopelessness, can be the result of continued and increasing Alcoholism and other addictions often develop as a result of overuse of alcohol or drugs to try to relieve stress Eating disorders, such as anorexia, are sometimes caused by stress and are often made worse by stress. If allowed to continue, then one's mental health is put at risk.