Gwen Stacy's death in the comics was a shock. She was dropped from a great height by the Green Goblin, and even though Spider-Man caught her with his web, the force of the stop was too much for her to survive.
Gwen Stacy's death in the comic was a result of a cruel twist of fate. The Green Goblin was responsible for her being thrown off the bridge. Spider-Man's attempt to save her wasn't enough to prevent the fatal impact that broke her neck. This event had a huge impact on the story and the character of Spider-Man.