虱子多了不痒，债多了不愁
shī​zi​duō​le​bù​yǎng​zhài​duō​le​bù​chóu

to be past worrying

虱子多了不痒，债多了不愁 虱子多了不癢，債多了不愁 shī​zi​duō​le​bù​yǎng​zhài​duō​le​bù​chóu
to be past worrying
one is no longer bothered by problems or debt when they become overwhelming; literally "when there are too many lice one does not itch, and when there is too much debt one does not worry"