A decade ago, a teenage Hayley ran away from home and her mother, Arlene Vaughan, and wound up on her uncle Trevor Dillon's doorstep.  Just to make trouble, she claimed on the front page of the National Intruder that she was Adam Chandler's daughter, but the joke turned out to be on her - she really WAS his daughter!  

At Pine Valley High, she got involved with fellow student Brian Bodine.  He proposed in 1992, but she turned him down.  On the rebound, he married An Li Chen to provide her with a green card.  Hayley threw herself at Will Cortlandt, nephew of Adam's rival, Palmer Cortlandt, and the two eloped.  He was murdered while trying to force himself on his bride, and she wasn't sure she hadn't killed him, as she was very drunk.  (Janet Green turned out to be the crowbar killer, in a misguided attempt to get close to Trevor.)

In 1995, Hayley got involved with Alec McIntyre, and the two became engaged, but on her wedding day Hayley left Alec, a victim of nerves and a premonition that she'd turn out just like her mother.  While sobbing on the beach in her wedding dress, she was accosted by a couple of thugs, but a waiter at the Valley Inn came to her rescue - Mateo Santos.  She and Alec did marry, but she had already developed strong feelings for Mateo.  Her marriage fell apart when, with the aid of Mateo, she found Alec had been having an affair with Arlene.  Hayley and Mateo found him trying to murder his lover and mother-in-law (and blackmailer) by pouring alcohol down her throat; the marriage was over and Alec went to jail.

Hayley and Mateo were just beginning to be romantically involved when Brian Bodine returned to Pine Valley, divorced from An Li and wanting to patch things up with Hayley.  Mateo stepped aside so that Hayley could follow her heart, but it led her straight to Mateo.  They were to be married in the spring of 1997, but Hayley was drugged and taken advantage of by best man Tanner Jordan. When Mateo learned that Hayley had been unfaithful, regardless of the circumstance, he called off the wedding.  Tanner kidnapped Hayley, but Mateo found out in time to save her (Tanner didn't survive the encounter) and the two were married in the hospital.

Lee Hawkins arrived in Pine Valley in 1998, bent on destroying Adam's family.  Hayley and Mateo, unaware of his identity and design, gave him a job in their new club, Holidays.  On the Fourth of July, Lee planned to blow up the club and kill everyone inside, but the warning came in time and everyone was saved.  Lee then kidnapped Junior and Marian, and in an attempt to help Junior, Hayley went with Lee.  He held her hostage, but Mateo, following dreams and visions he'd been having, managed, with the help of Edmund, to rescue her once again.  Lee had given her a rose tattoo, though, using toxic paint, and Hayley may never be able to bear children as a result.  

Hayley and Mateo planned to renew their vows, but plans changed when Mateo's first wife, Raquel, returned with Mateo's son Max in tow.  Hayley managed to forgive Mateo for failing to mention this first marriage (still valid), but seeing Mateo with son Max hurt her deeply, since she might never be able to give him a child.  All four of them - Hayley, Mateo, Max and Raquel - lived together at Wildwind.

When friend Ryan Lavery was accused of raping Kit Montgomery in 1998, Hayley stood by him.  Mateo wasn't convinced of his innocence, and his relationship with Hayley suffered.

In 1999, Mateo and Hayley opened their new club, the Sounds of Salsa.  The attention Mateo had paid to Raquel and Max was getting to be quite a strain on Hayley, though, even after she got the news that she could have children.  They decided to put off starting their family in order to concentrate on Max and his needs.  That summer, Hayley moved out of their condo, fearing her sobriety was in danger due to the strain.  On the Fourth of July, Ryan was there for Hayley when she needed a friend, and they shared a kiss.  They agreed it was a mistake and put it behind them, but when Mateo found out about it, he was pretty upset.  Eventually, though, Raquel and Max moved away, Ryan turned his attention to Gillian, and Hayley and Mateo were reunited.

They were married in a beautiful ceremony in the spring of 2000, but life hasn't been peaceful - Arlene has been on hand to stir things up once again.  Distrustful of her mother initially and the marriage to Adam, Hayley began to be won over when Arlene returned Stuart in time to save Adam's life, and then turned up pregnant.  Hayley and Mateo even had plans to adopt Arlene's baby and raise it as their own, but she miscarried as a result of a disagreement with Liza that led to a fall.  Hayley stood by her mother through the tragedy, but her trust was shattered when she learned that Arlene had actually miscarried the day before and schemed with Vanessa to blame Liza.