After disgracing her family by her public affair with a married foreign ambassador, Gillian was sent to live with her second cousin, Dimitri Marick. Upon arriving in Pine Valley, the first thing she did was try to sell Stuart a near-priceless religious icon, which he declined. Dressed in black leather, this Hungarian Princess went to Dimitri for shelter. Dimitri took her in with the exception that she had to find another place to live after a few weeks. Gillian did not make it there two weeks before Dimitri threw her out. Gillian was involved with the scam, along with Edmund and Tad, to make Dimitri tell the truth about Madeline not being his biological daughter, and the real reason he married Gloria. Dimitri found out that Gillian had something to do with this and he threw her out of the house. Gillian found out that her father had lost everything they owned due to a large gambling debt. Gillian then put her sights on Edmund, believing that she could make him love her and thereby get her hands on some money. That never happened. Edmund did, however, open up his home to her. Gillian started trailing Scott, seeing that he had a decent bank fund. Gillian and Scott got together and started dating. Kelsey Jefferson had her eyes also set to winning Scott's heart. Gillian saw Kelsey talking to madam at Holidays and went along with Kelsey to a private party to protect her. Derek Frye showed up and arrested the two girls for prostitution. The charges were dropped. Gillian and Kelsey have differences of opinions about each other. Kelsey, teamed up with Ryan Lavery, planned a trip to a ski lodge for the four of them, Scott, Gillian, Ryan and Kelsey, in hopes that Ryan could distract Gillian so Kelsey could get Scott alone with her. Scott feels that Kelsey and Ryan do not make a perfect match and decides to play protector. Gillian, while bathing in a tub, thought that Scott had come back into the room, and asked him to wash her back. Looking up it was Ryan Lavery.
After Gillian realized that it was Ryan that was in the bathroom with her while she was bathing, she started acting as though Ryan was going to seduce her, and started screaming for Scott. Scott barged through the door and threw Ryan out. Gillian thought about Ryan every waking moment. Kelsey saw that this little scheme was not going to work out. She opted for different, more extreme measures, trying to get Gillian deported. Scott found out about what Kelsey had done and told Gillian that he wanted to marry her, as soon as possible. Gillian was all for this. Gillian and Scott made quick arrangements to get hitched. Liza was worried about Scott marrying Gillian so she blackmailed Ryan into marrying her. Liza told Ryan that she would report his taking kickbacks from advertisers if he didn't go through with it. The day of the wedding, Ryan told Gillian that he loved her and wanted to marry her. Gillian was blown away by this and accepted, thinking that Ryan made enough money to support her. What Ryan didn't know was that this "princess" was penniless. Gillian pretended to hate Ryan with every part of her being, when down deep she really loved him. Ryan, after finding out about the penniless princess still decided to stay with her. He too, had deep feelings for Gillian. Matters started getting worse after Mateo and Hayley moved into Wildwind after Mateo sold the apartment they were living in. Gillian thought that Ryan had the hots for Hayley and this made her very jealous. While at Holidays for the grand re-opening, a "faulty" furnace (deliberately sabotaged by Lee Hawkins) exploded and Gillian and Ryan were both trapped in the debris. Gillian was trapped under a pile of heavy wood and left semi-conscious. Ryan stayed by her side until help arrived. Gillian was immediately transported to Pine Valley Hospital, with Ryan at her side. When Gillian finally woke up, Ryan was there holding her hand. Everything seemed fine as Ryan explained what had happened, until Hayley walked in the room. Gillian told Hayley to stay away from Ryan. Hayley didn't like the fact that Gillian thought she was trying to steal Ryan away from her, so Hayley gave Gillian a piece of her mind. Gillian told Ryan that she never wanted to see him again. That was until a dream she had of Ryan and Hayley, and Gillian walked out of the hospital to Wildwind, where she thought she could keep an eye on Ryan. Gillian was still very sick and she passed out. Ryan took her back to Pine Valley Hospital and it was there that Gillian finally knew that she really loved Ryan. She begged him to stay with her during her stay at the hospital and Ryan agreed.
Ryan learned of Gillian's affair with David Hayward and their relationship quickly went south. Ryan also feared that he could never have a real relationship with a woman because of the violent tendencies of the men in his family. It was revealed that Ryan's brother, Braden, had raped Kit Fisher (Jackson Montgomery's sister). Braden had no remorse, but managed to flee the country before he could be charged with the crime.
Gillian and Ryan were involved in a car accident after Gillian learned that Jake was not Colby's biological father. As a result of her injuries, Gillian was left unable to speak. Jake stood by her side and helped nurse her back to health. As a result, Gillian was unable to tell Jake the truth that she'd learned. Gillian and Jake were later married, but when Jake learned the truth about Colby --- and that Gillian knew the truth and kept it from him --- he went on a rampage. Jake left Pine Valley and during this time Gillian and Ryan found their way back to each other. Gillian anxiously awaited Jake's return to Pine Valley so that she could tell him that she wanted a divorce. Ryan was also anxious for the divorce so he went to Chechnya, along with Adrian, to bring Jake back. Ryan didn't plan on Gillian stowing away on the plane with them and discovered it when they landed. After they found Jake, he was injured while trying to rescue dozens of orphans in war-torn Chechnya. Gillian didn't want to hit Jake up for a divorce while he wasn't in tip-top shape… and Ryan slowly started to drift away as Gillian devoted most of her time to Jake. Finally, in October, 2000, Ryan told Gillian that their relationship was over.
Life for Gillian grew increasingly complex as she realized that she was still very much in love with Ryan. A night of drug-induced passion, left Gillian pregnant, but the father of the child was never determined. Gillian slept with both Ryan and Jake that night, but Ryan and Gillian always used protection. The pregnancy developed ectopically and Gillian lost the baby. Shortly thereafter, Jake granted Gillian a divorce.
On February 23, 2001, Ryan and Gillian were engaged and there were plans to have an elaborate wedding in Hungary. However, money problems with Incredible Dreams forced the couple to consider eloping at Town Hall. Dimitri and Alex caught wind of their plans and threw the couple a wedding to remember at the Wildwind chapel.
Married life proved rather uneventful for the couple. In fact, Ryan and Gillian acted as young adults, offering advice and other assistance to the likes of Laura, Leo and Greenlee. Troubled by Laura's life-and-death battle, Gillian decided to become an organ donor. It was her way of showing Laura that she was wishing her the best. At about the same time, Gillian befriended television producer Ilene Pringle, a woman who wanted to produce a reality television show set on Ryan's yacht, called Love Cruise. Ilene promised Gillian easy money if she'd allow her to produce a biography of her life. Wanting to be able to help Ryan with his financial difficulties, Gillian agreed - against Ryan's wishes. As it turned out, Ilene was not a television producer, but rather an assassin hired by Charlotte Devane to gun down Anna Devane, Alex's identical twin sister. On Monday, June 18th, Ilene mistook Gillian, who had her back turned towards her, for Anna and shot and mortally wounded her in the turret. On June 25th, Ryan made the difficult decision to have Gillian removed from life support so that her heart could be donated to Laura English.
Life after death proved extremely eventful for Gillian, who refused to believe that she was really dead. Jesse Hubbard, Natalie Dillon, Harold the dog, Jeremy Hunter, Cindy Chandler and Travis Montgomery -- all beloved Pine Valley residents who have passed away -- showed up in a pre-Heaven waiting area to help guide Gillian to Heaven. Gillian remained convinced that she could return to life and to Ryan and reached out to Opal to deliver her messages of love to Ryan. However, she finally came to terms with the fact that her and Ryan's relationship in the mortal sense was over and went back to Heaven vowing to love Ryan forever.