Prologue
Of the many little-known facts about Isabella Swan, there are many interesting tidbits; but by far the most significant one of them all is the happenings of an early September morning when she was barely seven years old...
Bella climbed out of bed, elated at the arrival of her birthday. She rushed down the stairs, blissfully unaware of the inevitable doom that would result from this simple action. She tripped a few steps from the bottom and fell, hitting her head on the banister.
Her mother was concerned, though sincerely less than shocked. She may have taken far longer to notice that something had gone wrong in her daughter's mind had Bella not immediately begun to weep and beg earnestly for forgiveness for scratching the banister so horribly.
"Bella, sweetie, what are you talking about? You could have gotten hurt, I'm not worried about the banister."
Stubbornly ignoring her mother's words, she continued to plead for her to not be angry. Worried, her mother drove her immediately to the hospital, where they were informed that Bella had received a concussion. This statement was made blatantly obvious when she commented that it was lucky she had gotten it on a Saturday, preventing her from having to miss any school.
By Monday, whatever problems Bella had been having were apparently all cleared up, and she went to school as usual. However, just a month later Bella reverted back to her mentally-damaged self. She cried herself into a state of absolute misery before inexplicably stopping and going back to her usual self. This happened a few more times before the mystery was solved: Bella suffered from a form of multi-personality disorder, triggered by stress. Whenever the stress grew too strong, her mind would switch to another personality as a coping mechanism.
So Bella was put on medication to keep the stress from building up. For ten years, her life was fine. However, Renée sealed her daughter's fate with a single mistake. That mistake was never telling Charlie about Bella's condition or the medication she needed. And so, when Bella moved to Forks, she was lost without her pills and fell into the hopeless insanity that resulted from too much stress in her actual self for her to change back to it.
That is the sad story of how she came to be the selfish, clueless, stubborn girl that fell for Edward Cullen. However, due to her rapidly approaching wedding, Bella's poor alter ego became as horribly stressed as her true self. Finally, the stress overwhelmed her second personality and she was forced back into her normal one.
The timing of the switch was nothing short of immaculate, for the night of the switch was directly before what was meant to be the night Bella Swan became Bella Cullen.