Info Mary Jane:
MJ came from a severely troubled family. Her father, a professor and frustrated writer, took it out on his family in the form of spousal and child abuse. To cope with her hellish family life, Mary Jane kept up a facade as a superficial party girl to avoid the embarrassment, which may have cast her as a forerunner to the archetype of a wily, feisty red head.
The parents eventually divorced. Mary Jane and her sister lived with her mother but often stayed with relatives. Her favorite was her Aunt Anna, who lived next door to the Parkers.
At first, she was unimpressed by Peter, a bookish nerd. That opinion changed dramatically on the night of Ben Parker's murder, and Mary Jane saw Peter become Spider-Man for the first time.
Source: wikipedia.org