Pour Cold Water On

Pour/Throw Cold Water on (Something) - to discourage or be negative about something, to make something less intriguing and cause to lose interest

1. His attitude poured cold water on me inviting him to the party.

2. His insistence on me eating burgers poured cold water on any chances of ever going out with him. 

3. The news of a couple getting mauled by wild dogs poured cold water on our plans of going camping next week. 

4. My injury poured cold water on my plans to go hunting next fall.

5. The not-so-well received pilot poured cold water on any chances of the show getting greenlit for another episode. 

6. The disastrous box office collection poured cold water on hopes of the movie getting a sequel. 

7. His health condition poured cold water on his aspiration of participating in the marathon.

8. David's fake apology poured cold water onto his hopes of forgiveness from people.

9. Rami's fame poured cold water on his desire to go into public places. 

10. Getting Duck in his last innings poured cold water on Bradman's chance to have an average over 100.