It was supposed to have been a spectacular Sunday in New York City for Paul DeSavino.
He and his mother, Marlene, were on their way to Carnegie Hall, where he was one of a group of piano students giving a recital. The others were already there, taking turns warming up. But Marlene DeSavino sensed that there was something wrong with her son, the only autistic performer in the recital that day.
"When we got to the rehearsal and he played, I knew immediately as soon as he played the first couple of notes that he wasn't focused," she said.
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Chopin's Prelude No.4 is one of the sweetest and gentlest melodies ever composed. And Paul was just chopping at it.
"I gave him clues and cues while he was playing it -- you know, 'Softer, good, good, that's right,'" Marlene said.
But the problem with Paul was entirely in his heart, as he had previously told his mother.
"He said that he thought that he was in love," Marlene said.
Paul told her later he was in love with an older woman. But problem was the woman didn't love him back. Unrequited love weighed devastatingly on Paul.
Who knew that a man with autism could suffer the pain of a broken heart? Does it even make sense that an autistic man is in love?
"Am I to say that what he thinks is love isn't love?" said Peter Gerhardt, executive director of Nassau Suffolk Services for Autism. "For him, it's love. And that's OK."
Gerhardt does not know Paul personally. But as one of the first psychologists in the nation to work primarily with autistic adults, he concluded long ago that autistic people are as likely as the rest of us to stumble into human attraction.
"First of all, it's part of human nature," Gerhardt said.
"He just wants to be with her," Marlene said. "He wants her to be around."
The object of Paul's infatuation is the director of a job-training program he was enrolled in for several years. It's a relationship that could never be, some of his closet confidants say.
"Feelings of love are so complex he doesn't understand the nuances," Marlene said.
And how do you explain that to a man who is otherwise always encouraged to go for it, to experience the pleasures and challenges the rest of us enjoy to the extent he can. Paul is told to enjoy things like sports and music.
He has a job as a volunteer errand-runner at a New Jersey hospital and lives with several adults in a supervised home of their own.
We filmed scenes of Paul in his home and at work for a "Nightline" special on autistic adults. This was a good time in Paul's life, before the heartache. But on that earlier visit -- when Paul showed me his room -- I learned that he'd had an earlier infatuation, with another teacher.
Paul is heartbreakingly naive in so many ways but especially about relationships.
To express his feelings for that earlier teacher he started wearing the same eyeglasses she wore, even though he has 20/20 vision.
"I can't believe how much I loved her," Paul said. "Well, she's a mother now."
The idea that autistic people love the same as everyone else is new to experts.
"The kids love their moms, they love their dads," Gerhardt said. "They will snuggle up. Yes, there is that classic distance, or they are not looking at them. But they'll sit next to mom and tuck themselves underneath their arms. That's love in his terms."
And yet a man like Paul, who loves in his own way, can seem so thoroughly at sea when trying to understand feeling like the feeling in a piece of music.
Jeff and Jessica, residents of a group home in New York, are dating. They are not the only mentally challenged members of the household to be in boyfriend-girlfriend relationships.
Christine lives here while Greg lives in an apartment nearby. He saw her at a group meeting, and they have been dating ever since.
There was a time when romantic and sexual involvements among the developmentally disabled were aggressively discouraged. Sexuality was taboo. The sexes were kept apart, and some individuals were sterilized.
"I worked for two other social service agencies, and rather than dealing with it, it was very ignored," said Lisa Stenrantino, who counsels residents on sexuality at the New York group home.
In addition to a general squeamishness, there were specific concerns about accidental pregnancy, disease and sexual abuse. The program at the New York group home, however, helps couples navigate the dangers with sex education and one-on-one counseling on when no means no.
Jeff and Jessica get coached on such topics as where to go, how to dress and how to respect one another in a restaurant and in the bedroom.
All this intimacy is within reach of the mentally retarded but is a world away from Paul's world. Autism doesn't impair intelligence, but it does affect the ability to communicate and make social connections.
The big problem for a man who seems to want to connect is how often he simply disconnects.
"He goes off into his own little world and that's the difficult part in having a relationship," Marlene said. "It's because he leaves them. He could leave them cold and he can't open himself up. He doesn't know how to do that yet."
Paul's mother has arranged practice dates but hasn't forced them. She has no particular dreams of marriage for Paul. And she's nowhere near contemplating a sex life for her son because he may never be ready for that.
But that's not the point.
"He's growing and that's the important thing," Marlene, Paul's mother, said. "And growth is very hard, and he'll tell me sometimes, 'This is too hard.' But God love him, he tries. He tries very hard."
Finally, at the recital, when it was Paul's turn to play for real in front of the full audience, he nailed his part -- thanks to his mother's support and encouragement.
That's what moms are for, isn't it? But it can also be what friends are for, too. Female friends. And maybe someday he'll find one of those.