St. Dymphna is a Christian saint recognized as the patroness of those suffering from mental illness and emotional distress. She is believed to have lived in the 7th century in Ireland and is often depicted with a lamp, symbolizing hope and guidance. Her story involves her fleeing from her father, who had become mentally unstable after the death of her mother. Her feast day is celebrated on May 15th, and many people seek her intercession for mental health issues. St. Dymphna is venerated in various countries, with numerous shrines dedicated to her, providing solace and support to those in need.