(CNN) -- Elliot Rodger's difficulties with women were so devastating to him that he vowed to kill anyone he couldn't win over.
"My orchestration of the Day of Retribution is my attempt to do everything, in my power, to destroy everything I cannot have," Rodger wrote in a 137-page manifesto obtained by CNN affiliate KEYT.
"All of those beautiful girls I've desired so much in my life, but can never have because they despise and loathe me, I will destroy."
He also said he despised men who had luck with women and said he would eliminate them, too.
"I will kill them all and make them suffer, just as they have made me suffer," he added. "It is only fair."
On Friday, that "day of retribution" came. Authorities say Rodger, 22, fatally stabbed three men in his home before killing two women outside a sorority house and then shooting a man at a deli in Isla Vista, California.
By the end of his rampage, six victims were dead. Rodger died of an apparent self-inflicted gunshot wound. And perhaps the only clues to the reasons are in the gunman's haunting dissertation of his life.
A life-changing divorce
For most of his early childhood, Rodger was a happy boy. But he said his first major traumatic event came when he learned at 7 that his parents were divorcing.
He described his parents' divorce as a devastating, "life-changing event," but said he gained more respect for his father after he quickly acquired a girlfriend.
"Males who can easily find female mates garner more respect from their fellow men, even children," Rodger wrote. "How ironic is it that my father, one of those men who could easily find a girlfriend, has a son who would struggle all his life to find a girlfriend."
Bitterness after puberty
But the impetus for most of Rodger's angst stemmed from his unfulfilled desires for women.
"As children we all play together as equals in a fair environment. Only after the advent of puberty does the true brutality of human nature show its face," he wrote.
"Life will become a bitter and unfair struggle for self-worth, all because girls will choose some boys over others. The boys who girls find attractive will live pleasure-filled lives while they dominate the boys who girls deem unworthy."
He described himself as a very jealous person, "and at the age of nine my jealous nature sprung to the surface."
Rodger wrote about the website PuaHate.com as a "forum full of men who are starved of sex, just like me.
"Many of them have their own theories of what women are attracted to, and many of them share my hatred of women, though unlike me they would be too cowardly to act on it. Reading the posts on that website only confirmed many of the theories I had about how wicked and degenerate women really are."
The site was down Sunday.
"I certainly would not want to blame a specific website for the violence and a tragedy that was carried out by one specific individual," Josh Glasstetter, a researcher at the Southern Poverty Law Center, told CNN. "But his online activities on forums like PuaHate gave his thoughts and beliefs more of a definition, and direction."
Traumatized by porn
When Rodger was 11, a friend he met through a chat room sent him photos of "beautiful naked girls," he wrote.
"When I looked at the pictures, I was shocked beyond words. I had never seen what beautiful girls looked like naked, and the sight filled me with strong and overwhelming emotions," Rodger said in his autobiography.
"I was traumatized. My childhood was fading away. Ominous fear swept over me. ... Indeed, a whole new world had opened up before me, and I had no idea how to prevail in it. I still wanted to live as a child."
The trauma got worse two years later, Rodger said, when he was at an Internet cafe and saw an older teen watching porn.
"The sight was shocking, traumatizing, and arousing. All of these feelings mixed together took a great toll on me," he wrote. "I walked home and cried by myself for a bit. I felt too guilty about what I saw to talk to my parents about it."
"Not getting any sex is what will shape the very foundation of my miserable youth," he said.
Taunting and bullying
Rodger said he endured a spate of bullying in the eighth and ninth grades, causing him to be "more shy and timid than I ever was in my life."
"I felt very small, weak, and above all, worthless," he wrote. "I cried by myself at school every day."
He said one of his worst days came at the end of ninth grade, when a classmate was bragging about having sex with his girlfriend.
"I defiantly told him that I didn't believe him, so he played a voice recording of what sounded like him and his girlfriend having sex," Rodger wrote. "I could hear a girl saying his name over and over again while she panted franticly. He grinned at me smugly. I felt so inferior to him, and I hated him."
That sense of inferiority carried over into his college days at Santa Barbara City College.
"Every day that I spent at my college, the more inferior and invisible I felt," he wrote. "I felt like such an inferior mouse whenever I saw guys walking with beautiful girls."
'Sophisticated, polite gentleman'
Some of Rodger's social media posts were more positive than the rants in his autobiography.
He portrayed himself as an affluent young man who drove a black BMW Series 3 coupe and traveled the world.
"I consider myself a sophisticated, polite gentleman, unlike most boys my age," according to a statement posted on "Elliot Rodger's Official Blog."
CNN cannot confirm the authenticity of the social media posts.
According to the blog, Rodger was born in the United Kingdom and moved to the United States at age 5.
He was raised in the shadow of Hollywood, in the affluent Los Angeles suburb of Woodland Hills, by his father -- a commercial photographer and sometimes director -- and his stepmother, an actress who appeared with Matt Damon in "Green Zone."
Pictures posted on Rodger's Facebook page show him with his father, Peter, on the red carpet at the premiere of the 2012 film "The Hunger Games."
Peter Rodger briefly worked as a second unit assistant director on the film, according to a spokeswoman with Lionsgate Entertainment, the company behind the "Hunger Games" movie franchise.
But it's also in the blog where Rodger railed against life in Isla Vista.
"I have tried very hard to fit in with the social scene there, but I have ultimately been unable to do so," the blog states. "There are too many obnoxious people who have ruined my whole experience at that place."
'Day of retribution'
The day before before the rampage, a video posted on YouTube featured Rodger ranting for nearly seven minutes against women who he said rejected him and popular kids who ignored him.
"For the past eight years of my life, ever since I hit puberty, I've been forced to endure an existence of loneliness, rejection and unfulfilled desires all because girls have never been attracted to me," he said.
"Tomorrow is the day of retribution. The day in which I will have my revenge against humanity, against all of you."
CNN's Joe Sutton, Sara Sidner, Alan Duke and Nick Valencia contributed to this report.