Because Elena didn't die by Enzo's hands like she was supposed to, his memories were restored. He remembered everything that Stella had made him do, every single one. He hated himself, but he hated Stella more, and in that anger, he did something he could have done a long time ago: he killed the bitch. Or so he thought.
Enzo rushed towards Elena's body, tears streaming profusely down his face as he shook her unconscious form, begging her to wake up. "Elena please, I'm sorry! Don't do this to me please! I can't leave without you!" He cried, not minding the blood that was quickly getting him stained. "I'm so sorry. I love you. I would never hurt you on purpose."
