In a 45-minute conversation, the 18-year-old told his mother he was gay, that he was having doubts about whether there is a God and that he felt friendless.
His mother thought it made her son feel better to tell her what was on his mind, though his secrets and sorrow were hard for her to hear.
"He left very comfortable and very relieved," she said. "I was very surprised, very much like someone had kicked me in the stomach."
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Joe and Jane Clementi have read some statements to reporters and issued more through their lawyer. But it's only now, 14 months after their son's death, that they have decided to grant interviews in an effort to promote The Tyler Clementi Foundation, which they have launched in their son's honor.
The goal of the foundation is to increase acceptance of gay young people, prevent suicide and stop online bullying.
The Clementis' family tragedy received a lot of media attention, and they now say they can see some good coming from it. "The positive would be that the publicity did generate interest in some of these big issues that need to be addressed," said Jane Clementi, a 53-year-old public health nurse.
Clementi's death spurred a national conversation about the treatment young gays and lesbians often endure.
Leaders from President Barack Obama to talk show host Ellen DeGeneres weighed in. The punk rock band Rise Against recorded a song, "Make it Stop (September's Children)" about the suicides of bullied young gays. In New Jersey, lawmakers say they adopted a school anti-bullying law in part because of Clementi's death.
The saga still is playing out in criminal court where the roommate, Dharun Ravi, faces 15 criminal counts, including invasion of privacy and bias intimidation, a hate crime punishable by up to 10 years in state prison.
The afternoon after Tyler broke the news to his mother, Joe Clementi, 55 and the public works director in Hawthorne, N.J., took Clementi for a car ride. "I told him, 'You've got to be careful. Not everyone is accepting as some people are."'
Two days after that conversation, they moved their son into Davidson Residence Hall C in Piscataway on the Rutgers campus, an hour's drive from his New Jersey home in the suburbs of New York City.