The English expression “don’t cry over spilt milk” is fairly commonly used and is generally given as a piece of advice. It is used in a metaphorical sense rather than relating to the physical spilling of milk.
The expression means don’t be upset over something which has already happened and therefore can’t be changed. It is generally given as advice using the phrase “It’s no use crying over spilt milk.”
There is no verified record regarding the origin of this expression although the earliest known record dates to 1888 in a book called Banking Under Difficulties. It is found in this book after a man has been robbed of his money and he then states “It was no use, however, crying over spilt milk.” This is the earliest record of the expression in its current form but a similar expression “no weeping for shed milk,” can be dated back to 1659 in a book called Paramoigraphy, by historian James Howell. At this time the verb “to shed” had the same meaning as “to spill,” although now the meaning of this verb has changed. It is unclear why the drink of milk was chosen as the spilled liquid although there has been speculation that the advice was generally given to children by their mothers after having literally spilt their milk.
An example of the expression in usage can be found in an article on the BBC news website from 2015 which centred around the claims from the British Party UKIP that there had been fraud involved in the by-elections. The quote in the article comes from Tom Watson, a member of the Labour party who accuses UKIP of “crying over spilt milk.”