At the time Tyler sat down to tell his parents he was gay, she believed that homosexuality was a sin, as her evangelical church taught. She said she was not ready to tell friends, protecting her son — and herself — from what would surely be the harsh judgments of others.

“It did not change the fact that I loved my son,” she said. “I did need to think about how that would fit into my thoughts on homosexuality.”

Yet it did not occur to her that Tyler would think she did not accept him. She had long talked with him about how his brother James was gay — though at the time James had not said he was. “Tyler knew we weren’t going to reject him or stop paying for college for him or not let him come home, because James had done all those things and we had a good relationship,” she said.

Tyler’s father, Joe Clementi, characterized the last month in his son’s life as a “rough spot.” But Ms. Clementi said she believed he was “confident, comfortable” in his decision. He left for Rutgers telling his parents about plans to attend events for gay students. He reported having gone to New York with new friends to see plays; his parents took this to mean he was adjusting well.

During a phone call one afternoon he sounded different. “A little sad,” Ms. Clementi said. “I thought maybe it was adjusting to being away. I told him how much I missed him, he got a little teary and told me he’d missed me, too. I thought he’d been away too much.”

That evening, Joe Clementi was awakened by a call from the Port Authority police, saying they had Tyler’s wallet and phone, that he’d been seen — then not seen — on the bridge.