idioms

back to the salt mines (have to return to work or something unpleasant): The lunch hour is over, boys. Back to the salt mines! We came back from our trip and went back to the salt mines.   envocabulary.com

heart sink (feel disappointed or discouraged) My heart sank when I looked at the huge pile of work on my desk. We decided to have a picnic down by the lake, but our hearts sank when it began to rain.   envocabulary.com

heartsick (very depressed or unhappy) She was really heartsick to learn of your divorce. He was absolutely heartsick over the loss of his ring.

Heartless (uncaring, inconsiderate, merciless) A heartless thief stole his wheelchair. Your father couldn’t be so heartless as to disown you.   envocabulary.com  

heartfelt (strongly felt, sincere) They sent a heartfelt message of thanks to everyone who helped. My heartfelt sympathy goes out to the victims of the war.     envocabulary.com