Details: They were high school sweethearts and believed they would grow old together and he fathered her first child; Lucas Scott, but Dan then abandoned Karen and their son to go off to college. He then met Deb and had a child with her. In Season 4, they grew really close again after Keith's death and dated for a while, until she found out he had killed Keith.
Details: When Dan left Karen Roe pregnant with his child to attend college, he met Deb. Soon enough, the two fell in love and Deb fell pregnant. Originally a happy family, Deb ended up working away from home to avoid seeing her son and bullied and pressurized by his father. Deb eventually returns to Dan and their marriage becomes sour. Unable to get away from Dan through divorce, Deb turns to pills and alcohol as well as Dan's brother, Keith Scott. Eventually, the couple split after years of distancing themselves, and they got divorced.
Details: During Dan first separation with his first wife; Deb Lee he met his neighbor Carrie who had watched him during his time at the beach house and they two went on a date until Deb came in and Dan realized he still wanted to be with her.
Details: Right after getting out of jail, Dan had his first sexual relationship in four years following meeting Patty and flirting her into bed but once he told her the reason for his incarnation their short-lived relationship was over.
Details: After fleeing Tree Hill, Rachel returned to her sordid life and worked as a stripper and prostitute. It was here that she encountered Dan Scott and, after he paid her to spend the night with him, they started to connect. Both deciding to get out of the dark places their lives were in they grew close as they reformed their lives. Rachel became heavily involved in Dan's self-help talk show Scott Free Redemption after their marriage but whether she really wants to help people is questionable as she seems more concerned with the success of the show. Rachel's romance with Dan serves her more for convenience than it does for love as it helps them portray the image they need to on the show and offers her all the privilege that Dan's money can provide her. However, after Dan realized that Rachel did not love him he filed for a divorce and, in giving all his wealth away after deciding it was wrong to profit of Keith's death, left Rachel with nothing.