The big words in the title simply mean this: Life goes up and down. That is the nature of human life on earth. Bad things happen to people, as good things happen to them.
But it is most amazing that the Qur'an addresses even this common human ailment -- life's difficulties -- like every other human situation that the Qur'an addresses and provides remedies and solutions for.
And when we say Qur'an, remember it also includes Hadith Sharif as divinely guided commentary and earthly substantiation of the Qur'an.
Allah's Double Promise in the Qur'an is this:
Surely, Life's Downs will be followed by Ups.
And surely with Difficulty will come Ease.
Allah's words are:
Fa-Inna Ma'al Usri Yusran,
Inna Ma'al Usri Yusraa!
Meaning, it seems to me: The sun will break through the clouds and Good Times will surely come with Bad Times.
When people face difficulties, whatever their nature or source, my standard answer is:
Turn to the Qur'an; read it; complete it if you can; and make Du'a. Allah's Rasul, Sallallahu Alaihi wa Sallam, says: Du'a done after reading the Qur'an, or after completing it, is answered by Allah.
Knowing of course Allah responds to all Du'as all the time.