On some level, it's possible to sympathize with Ye Wenjie for harboring so much hatred towards humankind. After all, she's been through so many traumatic experiences in recent years that it's hardly surprising that she should feel so thoroughly disillusioned with the world and everyone in it.
Ye's been through the hell of the Cultural Revolution, a massive political convulsion which turned China upside down and led to chaos and suffering on a monumental scale. During this dark period in Chinese history, anyone deemed to be an opponent of the country's leader, Chairman Mao, was in serious danger of torture, public humiliation, or even death.
It is the latter fate which is meted out to Ye's father, who is savagely beaten to death by Red Guards, the shock troops of the Cultural Revolution. Ye herself is branded a traitor and sent to a forced labor camp as punishment. Even after the Cultural Revolution finally ends, Ye's life doesn't get much better, as she ends up trapped in a loveless marriage to Yang.
Given what's happened to her, it's no surprise that Ye is so eaten up with bitterness and hatred for humankind. She is especially vulnerable, then, to the overtures of aliens from the planet Trisolaris who want to conquer earth. There's more than a hint of revenge on humankind in Ye's fateful decision to use her skills as a scientist to invite the aliens to come and take over the planet. Even though she's been warned not to do this by a pacifist from the planet Trisolaris, she does so anyway, in the belief that the aliens can solve hers as well as humankind's many problems.