Misfortune is that which good fortune depends on.
Unhappiness is that which happiness leans on.
Unhappiness is that which happiness relies on.
Unhappiness is that which happiness depends on.
Beyond the differences between using “fortune” (less personal : what happens to you) versus “happiness” (more personal : how you feel), there are also subtle differences : saying that one “relies” on the other is different than saying that they mutually support each other (as possibly indicated by the sentence following this one, not shown here).
Unlike the previous example, where the different translations for each symbol are more-or-less related, sometimes the choice the translator makes can affect the overall meaning or even the emotional impact of the sentence. In chapter 20, there is a line : 我 獨 若 遺 in which the last symbol can be variously translated into :
I alone seem lost.
I alone seem to have lost everything.
I alone seem to have been left behind.
I alone seem to be forgotten.