(CNN) -- Paul Sacco says searching for his daughter feels something like bleeding out. All the hope, heartache and anxiety that go into it leave him feeling diminished.
But the Colorado lawyer and amateur guitarist has managed to bottle up some of that energy, spending hundreds of hours creating what is both a tribute to Aubrey Sacco and a monument to his sorrow: a 14-song album he has published to Internet vendors.
"Finding Aubrey" includes 11 songs written and performed by Sacco at his home studio, as well as the last three songs Aubrey herself recorded at home before the 23-year-old disappeared in April 2010 while hiking alone in Nepal.
The case is unsolved, and the album -- for sale on iTunes and other outlets -- is a fundraiser for an investigation into her disappearance.
"So many people who know us say, 'What is it like?' or 'I can't imagine what it's like to have your daughter go missing,' " Paul Sacco said in a phone interview. "The album tells the whole story: feeling helpless, feeling like you want to celebrate your daughter, feeling like she may never come back and diminishing yourself as you look for her."
Aubrey disappeared toward the end of a five-month post-college trip in Asia. The 2009 University of Colorado graduate, who had a double major in psychology and art, went to Sri Lanka to teach yoga to vacationers before traveling to India to study yoga and volunteer to help schoolchildren with music and art.
She hoped to do charitable work, perhaps hooking up with a nongovernmental organization abroad, her dad said. But she vanished on the last stop of her trip, in Nepal's Langtang National Park, where she hiked for at least two days.
She initially was believed to have made it as far as a particular village on the hike's second day, but villagers there changed their stories and said they didn't see her after all. Investigators don't know what happened to her and have yet to find any physical trace of her.
Paul Sacco, 59, and his wife Connie have taken trips to Nepal to press the investigation, working with private investigators, Nepali police and the Nepali army to try to determine what happened.
Between his job and his investigation, Sacco found at least three hours a day for more than a year to create the album. Playing all the instruments, supplying all the vocals and recording and mixing the tracks, he grieved through music. He came up with a first version last year before publishing the finished product in April.
"My counselor said that he felt that was extremely healthy for me as an outlet, because that was how (Aubrey and I) related to each other, through music and art," Sacco said.
There are songs of tribute and nostalgia. "Crayons in the Sun" recalls Aubrey growing up -- painting, going to a father-daughter dance, wearing a homemade dress to graduation.
"I've written songs since I was 10 years old. I never wrote a song that I was crying onto the paper so much that the pen wouldn't write -- until then," Sacco said.
The album also shows moments of determination. In "The Great Divide," Sacco sings of moving heaven and Earth for her.
"Your pictures all hang in these empty rooms / I know you'll be here, soon," he sings.
In much of the album, though, Sacco works through despair and isolation.
"Now we're the car wreck on the road / people turn their heads and drive away from here," he sings in "A."
"Stare into the Darkness" speaks in part to the investigation's magnitude: "Stare into the darkness / and it'll stare right back at you / from the other side of the world / I think it's going to run me through."
Listeners also get to hear Aubrey, in songs that Sacco asked her to record before she left. They used to play music together, and he knew she was working on a few songs in the months before her trip.
"The night she was packing for Sri Lanka, I asked her, 'Honey, I really want you to record these songs,' " Sacco said. "She said, 'Why?' I said, 'Just in case something happens to you.' "
Aubrey's songs were rough recordings, not meant to be final products. But Sacco is grateful to have them and says they "give you a flavor of where she's coming from."
Sacco believes one of her songs, "My Heart Knows," was an "accept-me-for-who-I-am" sort of song, addressed primarily to a romantic interest but possibly to whoever listens.
"Please let me be me / person you're afraid to be / but don't worry, I know where to go / I know, because my heart knows," Aubrey sings.
Sacco, who didn't particularly want Aubrey traveling alone, said the song offers a good glimpse at his strong-willed daughter.
He has sold several hundred copies so far, and that's a few hundred dollars more for the family's investigation fund. He's grateful to have had the chance to explain what he's feeling though music.
Sacco hoped the disappearance would be solved by the time the album was done. Since he finished it, he hasn't been able to write much. The two relatively new half-songs he's written still are about Aubrey, but he says he doesn't have the energy to complete them.
"The biggest thing was to bury myself in my work at the law office (after the album)," he said. "That seems to be a good place to hide."