who cares

phrase2

1. •
   (informal) A reply to an unimportant or irrelevant statement, indicating indifference on the part of the speaker.
2. •
   (informal) A reply that dismisses the importance of another speaker's immediately preceding statement.

   • It makes no difference if you fall on the whirl. Who cares? And when you are through dancing you can go out to the faucet and get yourself a drink—provided the water hasn't been turned off. — 1922