Read the dictionary definition of regret. All definitions for this word.
1. sadness associated with some wrong done or some disappointment
1. he drank to drown his sorrows
2. he wrote a note expressing his regret
3. to his rue, the error cost him the game
2. express with regret
1. I regret to say that you did not gain admission to Harvard
3. decline formally or politely
1. I regret I can't come to the party
4. feel remorse for; feel sorry for; be contrite about
5. feel sad about the loss or absence of