Throughout the decades, Nicole Walker has created a very juicy romantic history. The character has had flings with men like Colin Murphy, Brady Black, and Austin Reed. She was even engaged to Dr. Daniel Jonas. Meanwhile, she's also walked down the aisle multiple times during her time on "Days of Our Lives" (via Soaps).
When Nicole first came to Salem, she had a mysterious past and came from an abusive home life with her parents. She fell in love with Eric Brady, however, she was still married to her first husband, Trent Robbins, whom she married while she was in college and was the biological father of Max Brady. Nicole later revealed that Trent was abusive toward her during their relationship, causing her to run away and go into hiding without filing for divorce, per Soap Central.
During her early years in Salem, Nicole agreed to marry Lucas Horton in exchange for $5 million. She needed the money, and Lucas was trying to steal Nicole away from Eric at the time (via Soaps in Depth). However, Victor Kiriakis found a way to take the fortune from Nicole, leaving her broke. She devised another plan and set her sights on Victor. The two married, but Nicole later learned that the marriage, as well as the one to Lucas, was deemed invalid due because she was still legally wed to Trent.