Lexi is an interior decorator and the ex-wife of Dr. Brett Cooper, who once had an affair with Kimberly Shaw, for eight years. Upon her arrival in Los Angeles, she became fast friends with Dr. Peter Burns, and a romance soon developed. However, her father died after collapsing during an argument with Peter, who Lexi quickly blamed. After discovering that her father actually had a medical condition, she later took Peter back. Their relationship ended when he developed new feelings for his ex, Amanda Woodward.
She soon learned that her father had positioned her to take the fall in an embezzlement practice, and that she needed to produce five million dollars or face arrest. She also discovered that Brett had been left an inheritance of ten million dollars, which he would receive only if he remarried her. In order to solve Lexi's problems, she and Brett agreed to a platonic marriage, as he was in a committed relationship with Megan Lewis at the time. As Lexi's feelings for her husband returned, however, she began taunting Megan, and eventually managed to seduce Brett. Feeling remorse for cheating on Megan, Brett told her that he'd get Lexi out of their lives, and soon took his wife sailing during a bad storm. Sensing that Brett would kill Lexi, Megan followed them and interfered, and Brett wound up leaving town afterwards.
Lexi later befriended Megan, and gave her a job at her company. She also discovered that Peter had played a role in the brief abduction of Amanda, and attempted to blackmail him into sleeping with her. She eventually opted not to expose him, as she didn't want him to wind up in jail. Lexi soon began a brief sexual relationship with Ryan McBride, who was also a romantic interest of her friend Megan. After moving back and forth between her feelings for Peter and Ryan, Lexi eventually gave up on both and became smitten with Dr. Michael Mancini. Before the two could be married in the series finale, however, Lexi admitted that she was likely to cheat on Michael, and backed out of the wedding. It is unknown where her whereabouts are curently. The circumstances under which the Melrose Place apartment complex transferred from Lexi's ownership over to that of Sydney Andrews are also unclear.