雨降って地固まる (あめふってじかたまる): adversity strengthens the foundations; after a storm comes a calm; what doesn't kill you makes you stronger

adversity strengthens the foundations; after a storm comes a calm; what doesn't kill you makes you stronger

Said after an argument or a crisis that left a relationship stronger than it was before. Reach for it once the storm has actually passed.

A Japanese proverb (ことわざ)