AN ONLINE AFFAIR WITH A SHOCKING TWIST THAT ENDS WITH A SUBURBAN MOTHER'S DEATH -- AND A BIZARRE LINK TO AN OLD CASE FINALLY RE-OPENED "48 HOURS MYSTERY," SATURDAY, FEB. 3

Jennifer and Bart Corbin had a seemingly perfect life. Bart's successful dental practice afforded the couple a beautiful home in the Atlanta suburbs where they raised their two little boys. But one December morning in 2004, seven-year-old Dalton Corbin woke up to a living nightmare. He ran to his neighbor's house in his pajamas and told them his mother was dead. Correspondent Peter Van Sant examines how a suburban mom suffered a fatal gunshot wound to the head and investigates her husband, a man who may have had something deadly to hide from his apparent charmed past. Van Sant also speaks exclusively to Jennifer's online lover - a person concealing a double identity. 48 HOURS MYSTERY: "Love and Lies" will be broadcast Sat., Feb. 3 (10:00 --11:00 PM, ET/PT) on the CBS Television Network.

"Do you think those boys are ever going to forget what it is to look at their mother after she's been shot in the head?" Heather Tierney, Jennifer's sister, said to 48 HOURS.

When officers arrived at the Corbin home that morning, it looked like Jennifer had killed herself. There were no signs of a struggle. There was a gun lying on the bed next to her. Bart had spent the night at his brother's house, which provided him with an alibi.

But as the investigation continued, police learned more about the Corbin marriage. That summer, Jennifer had told her family that she was planning to leave Bart. By fall, Jennifer had fallen in love with a man she had met on the Internet, and while the two had never met face-to-face, they were planning a real-life future together.

When Bart came across some emails that revealed his wife's online affair, he filed for divorce. Five days later, Jennifer was dead.

Police had their suspicions about Jennifer's apparent suicide. A few days after her death, the lead investigator, Detective Marcus Head, got a call from a woman with a tip. The caller suggested he look into the suicide of another Georgia woman 14 years earlier named Dolly Hearn.

Marcus contacted the sheriff's department, 150 miles away, that handled the Hearn suicide case in 1990. In an odd coincidence, the detective who answered the phone-Scott Peebles-was the son of the lead detective on the Hearn case. Peebles searched through his father's old files looking for a possible connection between the two deaths, and he found it. Hearn had broken up with her boyfriend just before her death, and that boyfriend was Bart Corbin.

Hearn's family had always been convinced that her death was not suicide and were grateful for the renewed interest in the case. When they were told about the death of Jennifer, Dolly's mother was stunned, saying, "It's happened again."

For investigators looking into the deaths of Hearn and Jennifer, it was hard to imagine the odds of two women committing suicide in one man's life. There could be only one explanation for this link. They believed Bart Corbin had staged both women's suicides, after they decided to end their relationships with him.

But investigators soon learned that Jennifer was going through her own personal agony in the last weeks of her life. She had found out that her online lover wasn't the man of her dreams after all. He was really a she. Jennifer never told anyone, but she did tell the female from the Internet, whom Jennifer believed to be a male all along, that the fact that he was a she, was tearing Jennifer apart.

Did Jennifer's discovery make her so despondent that she contemplated suicide? Or was the occurrence of two suicides in one man's relationship history a coincidence - or a deadly connection?"

The secret online lover speaks, for the first time on-camera, to Van Sant. She tells 48 HOURS about her online affair with Jennifer and about their last communications. She also reveals that Jennifer said she had suspicions about what soon might be her fate. But what were those suspicions? And did they come true?

48 HOURS MYSTERY: "Love and Lies" is produced by Loen Kelley and Jenna Jackson. The field producer is Michelle Feuer and the associate producer is Jessica Van Garsse. The senior producer is Judy Tygard. The executive editor is Al Briganti and the executive producer is Susan Zirinsky.