Caroline Forbes. She's been a vampire for 9 years and she still can't get over the fact that he left without saying goodbye. He was her true love and she hadn't seen him for 3 years. She searched for him the first year and gave up the second. The third year she met Peter and if she's being honest, she's happy. Klaus Mikaelson. He couldn't say goodbye. He didn't want to listen to her plead with him to stay because he knew if he listened, he would stay. He couldn't hurt her anymore, put her in danger. She had almost died multiple times because of him and he wouldn't be able to live with himself if she died because of him so he left. No goodbye, no letter, nothing.