In Buddhism, there is a concept called impermanence, which teaches us that nothing is permanent, and we should treat our lives as such.
On o positive side, our problems are impermanent, meaning that if today we feel bad tomorrow (or a week, month, ... after) we will be able to feel good again eventually!
On a negative side, the good things in our lives will pass, too. As such, we should not cling to things hoping that everything will last forever, as we are just preparing for one big disappointment.
Besides Buddhism, many other religions and folk stories are talking about this same concept in many different ways. Perhaps, my favorite story is by 19th-century retelling of Persian fable written by an English poet Edward FitzGerald. He writes:
Saving the life of the infamous rookie pirate, Captain Ruben Kirk, catapults Jessica Red into a sea of magic, jewel heists, and world-saving adventure.
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After years of watching pirates fighting with the king's navy off the coast of Harvest Island, Jessica Red saves the life of the infamous rookie pirate, Captain Ruben Kirk, and the two become fast friends. Little does she know, Ruben Kirk is only the first of three rookie pirates she'll meet during a whirlwind of sea-faring adventures - but when Jessica learns the corrupt King Mordred has plans to destroy her island home, can she convince them to help her save it?
("The Rookie Pirates" is Book 1 in "The Adventures of Jessica Red" trilogy.)
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