Bulgarian-born actress Nina Dobrev has announced she is to leave 'The Vampire Diaries' at the end of the sixth season. The 26-year-old actress, who stars as the protagonist Elena Gilbert in the supernatural US drama, has announced she won't be returning for the show's seventh season and has already staged a party to say goodbye to the cast and crew. She wrote on Instagram: ''I've just spent the most beautiful weekend on Lake Lanier in Georgia with my own TVD Family, the cast and crew of The Vampire Diaries. I want to be the first to tell you that it wasn't just a holiday celebration, it was a goodbye party. (sic) ''I always knew I wanted Elena's story to be a six-season adventure, and within those six years I got the journey of a lifetime. I was a human, a vampire, a doppelganger, a crazy immortal, a doppelganger pretending to be human, a human pretending to be a doppelganger. I got kidnapped, killed, resurrected, tortured, cursed, body-snatched, was dead and undead, and there's still so much more to come before the season finale in May.'' Dobrev - who previously dated her co-star Ian Somerhalder for three years until May 2013 - also took the time to thank the programme's ''passionate'' fans and promised the remainder of the sixth season will be great viewing. She said: ''You, the wonderful fandom who gave more love, support and passion than anyone could have ever imagined seven years ago, when a young 'Degrassi' girl from Canada showed up in LA to audition for 'that Twilight TV show.' ;-) I love you all. Fasten your seatbelts. If you think you know what's coming, you don't.(sic)''..