As originally conceived Peter Parker is a tragic character with some key events happening in Amazing Fantasy 15 (death of his uncle), The Amazing Spider Man 121-122 (Gwen Stacy death).
The following quote is from the Wikipedia article on issue 121-122 (my emphasis):
In the comic book collection The 100 Greatest Marvels of All Time: #9-6 (Amazing Spider-Man #121 was the #6 comic), Conway explained that Gwen and Peter were a "perfect couple", but taking that relationship to the next level (i.e. marriage or at least Peter revealing his secret identity to her) would "betray everything that Spider-Man was about", i.e. personal tragedy and anguish as root of Peter's life as Spider-Man. Killing Gwen Stacy was a perfect opportunity to kill two birds with one stone: breaking up the "unfitting" relationship and reinforcing the element of personal tragedy which was, in his opinion, the essence of Spider-Man.
So I wonder, are there particular literary influences or examples for the development of the character and the tragic makeup of his life?