The most common cause of homelessness is family rejection.
"We just live in a very divided society," said Siciliano. "In New York State, 54 percent are willing to support marriage equality, but that still means 46 percent don't."
"Even in a progressive state there is an incredible unwillingness to accept gay people as members of society," he said. "And if politicians and religious leaders go around saying it's unacceptable, and people give credence to that, how do they accept their gay kids?"
The center, founded in 2002, was named for Ali Forney, a gay 22-year-old who was murdered by a shot in the head on Dec. 2, 1997. He had been homeless since the age of 13, thrown out by his mother, and beaten up in foster care and group homes for his feminine behavior.
"Back then, there were no shelters and kids were stranded on the streets," said Siciliano. "They survived on prostitution and were addicted to drugs and infected with HIV. But most disturbingly, every few months kids were murdered on the streets."
Cocco has had close calls with assaults. One night riding the subway, her backpack was grabbed with such force that she was thrown from her seat.
"New York City is the birthplace of the gay rights movement and has a powerful gay community here," said Siciliano. "It's just so wrong that these kids are suffering."
The center runs two drop-in centers and a mental health clinic that also provides free medical treatment, as well as two housing programs, one for emergencies and another transitional facility.
They rely federal, state and some city funding, which has been substantially cut back during the down economy, and on private donations.
One gift -- $100,000 from gay activists Frank Selvaggi and Bill Shea -- arrived on the 14th anniversary of Ali Forney's death. They hope to raise even more funds for more shelter beds.
The couple saw a recent news special on homeless youth.
"It was completely devastating to see how these bright young kids had to fend for themselves," said Selvaggi, 52.
After meeting Siciliano, they made their decision to divert donations from Selvaggi's high school and to donate to AFC in 15 minutes.
"There's an urgent need for these kids, especially in New York City, where they are sleeping in the subways, rooftops and selling themselves for sex," said Selvaggi, a CPA. 'It's heartbreaking."
"We didn't know the facts and horror stories," said Shea, 52. "It blew our minds and we've got to wake up the community."
The couple, who were married seven years ago, said they found it hard to comprehend the cruelty of parents who reject their children.
"Frank and I were very lucky in our lives when we came out," said Shea, who the director of creative services for Autism Speaks. "Our parents were great. I am part of his family and he mine."
Cocco said that with a more stable life, she has now reconnected with her own family. And being part of the "Homeless at the Holidays" project has given her new hope.
"All these interviews [with homeless youth] inspired me to make a difference," she said, "to let people know that the kid sitting next to you on the train is probably homeless. Don't be fooled just because they don't smell like pee and wear nice clothes."