Eye Movement Desensitising and Reprocessing (EMDR) is a trauma-focused therapy. It is well known as a therapy for treating PTSD but is also very effective for other mental health issues.
The therapy works by using bilateral movements with the eyes or other parts of the body (e.g. hands, feet) or equipment to reprocess a traumatic event.
If the therapy is successful, when you think about the event that happened, all emotional charge is gone and you will have a different perspective on the event which allows you to feel calmer when you think about it.