Zero fucks given
The inability to give even one fuck about someone or something, i.e. the situation in which one is unable to care. This term is also used to express dismay, disbelief, or sarcasm pertaining to someone or something, and can be a successful comeback comment in the event of a downward-spiraling conversation.
Michael: "Vicki, you were the one that broke up with me!"

Victoria: "Zero fucks given, Mike."