In the comics, Peter Parker meets her, and falls for her right away. The two start dating shortly after, until Peter leaves her for Gwen Stacy. MJ begins dating Harry Osborn, but remains friends with Peter.
After Harry and MJ break up, and Gwen's death, MJ and Peter begin dating again. She gets upset that he often ditches her, but forgives him when she finds out that he is Spider-man. The two eventually get married.
In Other Media
Mary Jane in the 1990s animated series
Animated Series
Mary Jane was a major love interest in the 1990s Spiderman animated series. After having an on-and-off relationship with Peter, MJ was killed by the Green Goblin when he dropped her into a black hole he had created. MJ later reappears alive and well and Peter becomes much more devoted to her. They eventually got married. This happiness is short-lived as this MJ is revelaed to be a clone whose cellular structure was unravelling. She eventually turned to liquid, leaving Spiderman depressed.
Mary Jane in the film
Film
Mary Jane also appeared in Sam Raimi's Spiderman trilogy, where she again appears as his love interest. In the films, she is played by Kirsten Dunst. MJ and Peter have been neighbours for years, but have seldom talked to each other.
She was originally dating the high-school jock "Flash" Thompson, but the two split up after graduating. She then starts dating Harry Osborn, but the relationship seems to be mainly for show as she has recently fallen for Spiderman. After Harry senses that Peter and MJ are getting closer, he finally breaks up with her and starts plotting against Spiderman, whom he believes is guilty of killing his father.
MJ admits that she loves Peter shortly after surviving an encounter with the Green Goblin. Peter reluctantly turns her down, knowing that keeping anyone close would only endanger them now.
In Spiderman 2 Mary Jane has become a fashion model and stage actress. She's now engaged to John Jameson and seems to have given up on Peter. After Peter temporarily quits being Spiderman, he tries to reconnect with MJ but she winds up being kidnapped byDr. Octopus. Spiderman comes to her rescue but his mask is lost in the scuffle, revealing himself to Mary Jane. Peter then tells MJ that he can't stop being Spiderman and that they aren't meant to be. Despite this, Mary Jane realises on her wedding day that she loves Peter more than she loves John and leaves her fiancée at the altar. Touched by Mary Jane's gesture, Peter finally gives in and agrees to be her boyfriend. Their relationship kicks off!
In Spiderman 3 Peter is planning to propose to Mary Jane, but has failed to notice that things aren't going so well for her. Her latest performance received negative reviews and she's begun to notice Gwen Stacy eyeing Peter. After losing her part in the play and having to take a job as a waitress, she finds Peter to be too self-obsessed and decides to start hanging out with Harry. Harry and MJ have a romantic moment and kiss, but MJ back out when she realises what she's doing. Harry then breaks into her apartment and threatens to kill Peter if she doesn't break up with him.
After Peter's heart was broken, he donned his new black alien suit, which caused him to become more agressive and spiteful, injuring Harry and flirting with random women. He then takes Gwen to the club MJ is waitressing at and dances with Gwen to make MJ jealous. After getting into a brawl with some bouncers, Peter accidentally hits MJ and realises what he's become, running away in shame.
MJ is then kidnapped by Venom and the Sandman in an attempt to get to Spiderman. Spiderman beats them both with the help of the reformed Harry Osborn and slowly begins rebuilding his relationship with MJ.
