With accent marks:
Слеза́ми го́рю не помо́жешь.
You can't help grief with tears.
This Russian proverb reminds us that belated lamentation and tears often can not change anything in the situation. Better to wipe away your tears and move on, trying not to repeat past mistakes and make the best of what's given to us.
Similar proverbs are found in many other languages.
Other Russian proverbs
Crowded, but not aggrieved.
What goes around comes around.
A wolf is fed by his legs
Don't go to the woods if afraid of wolves.
If I knew where I would fall, I would lay some straw there.
Beast runs towards the hunter.
You see your friends in the times of trouble.
Repetition is the mother of learning.