Green’s Dictionary of Slang

tough shit! excl.

also hard shit! tough! tough shitski!
[tough shit n.]

so what! see if I care! a response indicating little or no sympathy with the first speaker; also attrib.

[US]M. Richler Apprenticeship of Duddy Kravitz (1964) 95: You make fun of your father. You don’t like him. Tough shit.
[UK](con. WWII) G. Sire Deathmakers 115: ‘Drive carefully — you might hit a kraut.’ ‘Tough shit.’.
[US]R. Gover One Hundred Dollar Misunderstanding 95: Weekend is one hunner, an if the trick don’ stay all weekend, tough shitski, it still cost him one hunner.
[US]L. Heinemann Close Quarters (1987) 158: And the big guy says, ‘Tough shit, kid.’.
[UK](con. WW2) T. Jones Heart of Oak [ebook] ‘Christ, I can’t stand heights’ [...] ‘Hard shit’.
[US]L. Heinemann Paco’s Story (1987) 188: For Christ’s sake [...] fuck you and the horse you rode in on. Tough shit, bub.
[UK] (con. 1950s) D. Farson Never a Normal Man 212: ‘Tough shit,’ he said. [Ibid.] 312: Deakin was in his ‘Tough shit, kiddo’ mood.
[US]C. Hiaasen Nature Girl 135: Tough shit. I was here first.
[Aus]L. Redhead Thrill City [ebook] ‘I’ll be recommending you for an award.’ ‘I’d rather you didn’t.’ [...] ‘Tough shit’.