The Vampire Diaries: The Salvation Series by L.J. Smith, Aubrey Clark

The greatest threats are the ones unseen…. For what seems like the first time, Elena and her friends are happy. Elena and Stefan have built a home for themselves in Dalcrest, and all of Elena’s friends are as in love as she and Stefan are. Even Damon is enjoying visiting his favorite old haunts in Europe, and is more surprised than anyone that he’s traveling with Katherine. But lately, Elena’s Guardian senses are on edge, and she can’t ignore the feeling that danger is coming... moreThe greatest threats are the ones unseen…. For what seems like the first time, Elena and her friends are happy. Elena and Stefan have built a home for themselves in Dalcrest, and all of Elena’s friends are as in love as she and Stefan are. Even Damon is enjoying visiting his favorite old haunts in Europe, and is more surprised than anyone that he’s traveling with Katherine. But lately, Elena’s Guardian senses are on edge, and she can’t ignore the feeling that danger is coming. When a new threat arrives in Dalcrest, Elena’s worst fears become a reality. Soon, she and Stefan are battling a vicious Old One who is always just out of their reach. And when Damon and Katherine are confronted with a strange and mysterious enemy, Elena worries the attacks are linked. As dark forces close in, Elena, Stefan, and Damon struggle to survive the only way they know how—together. But their lives are hanging in the balance, and every moment they share could be their last… less

The New York Times bestselling series continues ..... An epic battle looms - one that will not only determine Elena's own fate, but that of her entire world. Since her true love Stefan was staked through the heart, everything has changed for Elena. Stefan was hunted down by a scientist who has created a new race of genetically-engineered vampires to take over the paranormal world. Intent on eliminating all the natural vampires left on earth, Damon is the scientist's next target... moreThe New York Times bestselling series continues ..... An epic battle looms - one that will not only determine Elena's own fate, but that of her entire world. Since her true love Stefan was staked through the heart, everything has changed for Elena. Stefan was hunted down by a scientist who has created a new race of genetically-engineered vampires to take over the paranormal world. Intent on eliminating all the natural vampires left on earth, Damon is the scientist's next target. It's a race against time to find the kryptonite of these strange creatures, before they hurt everyone Elena loves. less

Love is a very powerful force... Ruthless scientist and vampire creator Jack Daltry is dead, killed by Damon and Elena. But now Elena is dying, and the Guardians have given her one chance to save both herself and Damon. She must go back into the past, back to before she met the Salvatore brothers. Elena must ensure the destruction that was started with Stefan and Damon's obsession with her will never begin. But can she bear to create a future where she's not with either of them?