The man was awakened by an accident and left the group in a strange way.
From the initial doubt, surprise, satisfaction, fear and even complacency, I finally couldn't bear the feeling of loneliness, and decided to try to wake up the hostess. This is more like an elaborate "lonely game".
You know, after thousands of years of evolution, human beings have already become unique social animals. Only by living in groups can we have complete consciousness and enjoy complete freedom.
Therefore, the feeling of loneliness on the surface is actually more like an instinctive reaction to regain physical and mental balance at any cost after being unintentionally "exiled" by the whole human race.
The complexity of human nature is revealed from the man waking up the woman to the man revealing the truth and finally choosing to sacrifice himself to save the spaceship.
It is human nature to seek advantages and avoid disadvantages. In addition, the instinct of discovering that he is a human makes the man take risks and successfully wakes up the woman's body. However, it also means that the woman's life is bound to be on the verge of destruction.
After the lie was exposed, facing the cruel truth, the man finally chose the best result. In doing so, he not only intended to wake up the woman "atonement" for himself, but also hoped to save nearly 5,000 lives left on the whole spaceship through his own sacrifice.
Although, to be a hero, the man has never thought about it, but from avoiding the truth to facing sacrifice, it looks more like the self-sublimation and self-salvation of human beings represented by the man.