Something got me started thinking about my own pet theory about Phoebe and Ursula, and that got me to thinking about the rumors about Rachel being killed off.
Friends killing off a major character would never happen, unless the actor was killed and the character needed to be eliminated (like Bill on NewsRadio).
I came up with a very un-Friendly way to kill off Friends:
First, complications with Rachel's pregnancy become fatal for her and the baby.
The guilt causes Ross to have a total nervous breakdown (if he hadn't gotten he pregnant, she wouldn't have died). He realizes that Rachel was one of the only two women he ever really loved or could love, so he decides he has to get the other one, Carol, back. So he goes and kill's her life-mate.
Meanwhile, Monica is extremely distraught over her best friend's death and her brother's psychosis, that she starts pushing Chandler away. Chandler goes looking for sympathy elsewhere, finding it in the arms of Ursula.
Except it isn't Ursula, because Ursula is just Phoebe's other personality. Phoebe was molested by her father, which led to her real mother abondoning the family, and her other mother's eventual suicide. All this trama caused the Phoebe/Ursula personality split.
Originally, Phoebe was the bad girl (street Phoebe) and Ursula was the innocent one. But then Phoebe met Monica and began shifting her wild ways to her Ursula persona (explaining the disparity between Mad About You's Ursula and Friends' Ursula).
Of course, the Chandler/Phoebe affair ends his marriage to Monica.
Joey, meanwhile, either discovers that during all his sleeping around, he's contracted AIDS, or realizes that his promiscuity is because he's been unable to accept his homosexuality. If the latter, his realization comes when he's trying to comfort Chandler and tries to kiss him.