Post-traumatic stress disorder (PTSD) is a debilitating mental disorder that follows experiencing or witnessing an extremely traumatic, tragic, or terrifying event. People with PTSD usually have persistent frightening thoughts and memories of their ordeal and feel emotionally numb, especially with people they were once close to.
Most people with post-traumatic stress disorder repeatedly re-live the trauma in the form of nightmares and disturbing recollections during the day. The nightmares or recollections may come and go, and a person may be free of them for weeks at a time, and then experience them daily for no particular reason. They may also experience sleep problems, depression, feeling detached or numb, or being easily startled. They may lose interest in things they used to enjoy and have trouble feeling affectionate. They may feel irritable, more aggressive than before, or even violent. Seeing things that remind them of the incident may be very distressing, which could lead them to avoid certain places or situations that bring back those memories. Anniversaries of the event are often very difficult.