Bonnie Bennett

Bonnie Sheila Bennett is a very powerful witch and one of the main female characters of The Vampire Diaries. While she filled the role of counselor and confidante to all of her friends, Bonnie is a feisty, yet empathetic witch, who discovered her powers just in time to help out her family and friends. She is best friends with Caroline Forbes, Elena Gilbert, Matt Donovan, Damon Salvatore, and her ex-boyfriend, Jeremy Gilbert and has known most of them since childhood. She is also close friends with Stefan Salvatore and Tyler Lockwood. Bonnie was in a romantic relationship with Lorenzo St. John before his death.
Bonnie is noted for having many heroine tendencies, such as being very compassionate, empathetic, helpful, and very selfless (to the point of martyrdom). Bonnie is repeatedly ready to sacrifice herself for her family and friends without any hesitation. As her powers grew, she's stepped up at every opportunity to protect her friends, even if it meant trading her life in the process. Her spell-casting abilities most definitely came in handy when the Originals came to Mystic Falls. Gaining the power of Expression, she was able to take down two Original vampires, as well as the very first immortal, Silas. Despite the warnings from her Grams, she combined spirit, Expression, and dark magic to resurrect Jeremy back from the dead. While successful, it was too much for her and the spell killed her in the process. 
Existing on the Other Side as a ghost, her very ancient and powerful ancestor, Qetsiyah, transferred the status of Anchor to the Other Side from Amara to Bonnie, allowing her to exist on both sides of the living and the dead. However, Bonnie was forced to feel the pain of every supernatural death and no longer had access to the powerful magic she once had. After Markos violently tore his way out of the Other Side with the help of the Travelers, it began falling apart. His unnatural resurrection unbalanced the Other Side which threatened Bonnie with permanent death. Despite great effort on both her and her friend's part to save the Other Side, it eventually imploded on itself as Bonnie and Damon spent their last moments together. However, Shiela's last act made sure that Bonnie would be fine. Before it's destruction, they were engulfed by a white light.
Bonnie and Damon found themselves back in Mystic Falls. However, they were forced to repeat the same day, May 10, 1994, over and over. Though Damon retained his vampiric abilities, Bonnie was unable to perform magic. Eventually, they learn that this world is inhabited by another, Malachai Parker. When Kai attempts to kill Damon, Bonnie arrived just in time and regained her magic at the prospect of losing the only friend. Bonnie learns that she, rather her blood, is the key to free themselves from the prison world, using a Gemini artifact, called the Ascendant. Sacrificing herself, she sends Damon back to the mortal plane and is forced to endure Kai's torturous pursuit until she's left alone in the prison world without her magic. Reminded by her friends, she travels to Novia Scotia and retrieves Qetsiyah's calcified blood and reclaimed her own magic, freeing herself from the prison world. Her experience with Kai and her time in the prison world, however, drastically changes her. She decides to puts herself first but continues to suffer signs of PTSD, such as being unable to adjust to other people. With time, Bonnie falls back into her old life, but not before imprisoning Kai in the 1903 Prison World. However, he escapes as had Bonnie did, an links her life to Elena's. As long as Bonnie was alive, Elena would be forced to slumber in a magical coma.
With the return of the Heretics, a coven of siphoner-witch, vampire hybrids, Bonnie and her friends eventually turn to the Armory for help. However, in exchange, they want Bonnie to unseal the Armory's vault that was magically sealed by Lucy. Refusing to unleash a monster, Bonnie went into hiding with Lorenzo St. John. Over the course of three years, they developed a romantic relationship. Enzo eventually learned that the Armory's anti-magic pills that was helping Bonnie hide from them was also poisoning her, an illness that could not be cured and would eventually kill her. Rayna agreed to transfer her last life to Bonnie. As the spell is completed, Rayna revealed that Bonnie became the new shamanic huntress in her place. After Damon destroyed the corpse of the last shaman, Bonnie's connection to it also broke, freeing her from her duties and abilities as the huntress.
However, her magic did not return, leaving her devastated over the loss of her powers as well as Enzo and Damon being taken by the Armory's monster, Sybil. Bonnie was eventually reunited with Enzo after he was freed from Sybil's mind control. However, upon his tragic death at Stefan's hands, Bonnie unleashed a psychic blast, preserving Enzo's spirit in a newly created dimension. Eventually, she and Stefan fight Arcadius, the Devil himself, which led to Stefan killing him, though Hell was not destroyed — Katherine was its new ruler. Letting go of Enzo, Bonnie is able to regain her magic. With her magic restored and with the support of her many ancestors across the centuries, they managed to destroy Hell itself and Katherine along with it. Bonnie's eventually able to free Elena from her magical coma, sparing both of their lives. Determined to keep her promise to Enzo, she decided to live her life to the fullest and wanted to see the world and enjoy her life.
Bonnie is a member and the last surviving witch of the Bennett Family.