if the going gets roughif the going gets rough/tough
when the going gets rough/tough - when a situation becomes difficult or unpleasant.
I'm spending Christmas with my family, but if the going gets tough I might escape back to London.
if the going gets rough
If things become too difficult or unpleasant to deal with; if it becomes too hard to keep carrying on. Everyone in our neighborhood is very close, so if the going gets rough for anyone, there's always someone to lend a hand.I trust you'll be able to handle this on your own, but give me a call if the going gets rough.