When two people are together, one person says what cold salad means.

Cold salad means that you don't care or ignore it and take an inaction attitude to deal with the problem.

For example:

My mother has been urging me to go home today. If I go home, we can't be together. What should I do?

-What else can I do? Cold salad. There is nothing at home now, but your mother misses you.