Sydney, Australia ? Olivia Newton-John said her singing is helping her cope with the mysterious disappearance of her longtime boyfriend.

Patrick McDermott, 48, failed to return from a June 30 fishing trip off the California coast. It is being investigated as a missing person case.

Newton-John told an Australian TV network that her grief was so intense she did not think she would ever sing again, but she said that was “terrifying.” She said singing is her soul and music is a “very healing thing.”

Newton-John, 57, appeared opposite John Travolta in the 1978 movie “Grease.” She is best known for songs such as “I Honestly Love You” and “Physical.”