Siziphus himself, would have already given up, but not you. Moreover, the adultury will become a secret code, the system of signs that will keep you two together in this labyrinth of your relationship, in the bitter delights/passion, rough pleasure, pure paradoxes. Together you will go through alchemical phase of mutation of your marriage from something into nothing, from marriage into trick, shuddering from thrill because it is all an illusion, fantatsy, day dreaming.
Siziphus himself - even the most persistent person (or anybody else in the world)
In Greek mythology, Sisyphus was a man the gods punished. They assigned him the job of rolling a large rock up to the top of a mountain. Moreover, they arranged things so that, just when he succeeded in getting the rock almost to the top, the rock would roll down again. This supposedly went on for eternity, since he never was able to get the rock to stay at the top of the mountain!
delights/passion - joys/very strong, intense feelings
alchemical - dramatically transformative, changing
(typos: adultery, fantasy)
This isn't easy reading, even for someone who learned English as a first language. More power to you!