The Vampire Diaries: 10 Worst Things Bonnie Has Ever Done

4. Forced The Cure On Stefan

Under Cade's spell, Stefan kills Enzo, the love of Bonnie's life. The cure was meant for Enzo to live a mortal life with her, but with his death, Bonnie takes vengeance at the moment and turns Stefan back to a human. She doesn't make the choice simply out of self-preservation, but out of revenge.

She knows that with his humanity returned, Stefan will feel the overwhelming remorse of killing Enzo and be left vulnerable to attack. It's a complicated situation as Stefan is set to marry Caroline.