In one corner we have the blonde bombshell known as Gwen Stacy. In the other corner we have the crimson she-devil known as Mary Jane Watson. Both are considered primary love interests of Peter Parker/Spider-Man. But who can officially be considered the "one true love" of Peter Parker?
Team Gwen
Gwen Stacy will always be considered Peter Parker's first love. But was she his true love? Gwen was incredibly similar to Peter in that she shared the same love for science. When Gwen was still alive, she and Peter were on the verge of getting engaged. But then that fateful day came, and any one who knows comics knows what I'm talking about. Gwen Stacy holds the great honor of being one of the only important comic book characters to ever stay dead. Some see this as proof that Marvel doesn't care about Gwen anymore, while fans of the character believe that this honor is what makes her so unique and special. Gwen's death has had a profound effect on Peter Parker. As far as important events in Peter's life, Gwen's death is rivaled only by that of Uncle Ben. To this day, Peter still mourns Gwen's death and has claimed on more than one occasion that he still loves her. When Scarlet Witch temporarily altered the fabric of reality to recreate her lost children, Gwen Stacy never died and she and Peter lived happily ever after. However, it's unknown what other factors might have contributed.
Team MJ
Technically speaking, Mary Jane actually came first. But when their little romance ended, they became best friends. Even when Peter was with Gwen, MJ rivaled with her as the other most important girl in his life. When Gwen died, the one person who always met Peter with sympathy and understanding was Mary Jane. The spark that existed between Peter and MJ grew into a bonfire. They soon fell in love and after many years they finally got married. It can be argued that Mary Jane and Spider-Man are the most famous couple in comic books. Their relationship has had its pitfalls, but they always fought through it together. It is said that what doesn't kill you only makes you stronger, and nothing could describe the relationship between Peter and Mary Jane more perfectly. Their lives have been struck with so much tragedy and torment in the past, such as their child's murder at the moment of birth by the Green Goblin. Such tragedies would tear almost any couple apart, but they've always managed to fight through those struggles and disasters and have grown even stronger. On one occasion, the love of Peter and MJ had even been steered with a little divine intervention. It's hard to argue with God on these matters.
Note: Both Mary Jane and Gwen have been met with character assassinations. For Mary Jane this story would be called One More Day. For Gwen Stacy this story would be called Sins Past. Both stories are considered some of the most appalling comic book arcs ever written. For the sake of fairness in this argument, we will pretend that both stories are not in continuity.