used to show that you do not feel sorry for sb who has a problem; used to show sympathy for sth unfortunate that has happened to sb
Oxford90% of films
used to show that you do not feel sorry for sb who has a problem
Tough luck, Yeager. We all have family.
Oxford10% of films
used to show sympathy for sth unfortunate that has happened to sb
Tough luck for you, dude. Sorry.
Definitions from the Oxford Advanced Learner's Dictionary, 9th edition