Katherine Gets Burned, 1979
Derek's crazy ex, Suzanne, sent Katherine to a mental institution by poisoning Kay's chocolates (tainting the woman's favorite food was just extra cruel). When the asylum burned down, Kay managed to escape, but faked her death — all so she could see how Derek felt about her. Kay was pleased when she overheard him defending her to Suzanne, then "haunted" ol' Sue by making ominous phone calls and even leaving tarantulas in the bed (yikes!). However, in Kay's "absence," Derek had moved on to Jill. When Kay revealed herself, she and Derek soon reunited, but the love triangle continued.

All About Eve, 1983
When Victor found out that his ex, Eve Howard, was poisoning him, he faked his death (complete with a wake and casket!), then kept "appearing" to her. She was eventually committed.

Menaced By Matt, 2001
Poor Tricia. After Matt drugged her and then slept with her, she tried to kill him by driving their car off a cliff (the fact that she had spied him trying to rape ex-girlfriend Sharon may have had something to do with that). Matt perished in the hospital (by pulling out his own support tube and making Nick look like the killer), but continued to taunt Tricia in visions. He convinced her to "get" the Newmans, which Tricia indeed did when she killed Ryan on the day he was supposed to wed Victoria.

Body Of Evidence, 2003
Sharon had an affair with Cameron Kirsten, but when he beat her and later tried to rape her, she understandably hit him over the head with a bottle of champagne. She hid the body, but was haunted by Cam's rotting corpse (yuck!). Turns out Cameron was alive (and in cahoots with her past romantic rival for Nick, Grace). Cam attempted to set Sharon up for the murder of the real corpse she had spied — Frank, father of her daughter, Cassie. Sharon and Nick managed to capture Cameron and turn him over to the cops.