Rosalie Cullen was probably the only one who supported Edward's decision to leave. She had always known that it was a horrible, horrible idea to get involved with the girl. She tried to tell them, but they were so happy that Edward was not alone anymore, they didn't think about the consequences. If she was honest to herself, none of the things she worried about came true. Isabella didn't blabber about their secrets to anyone. She never made anyone in their family less because of what they are, the opposite actually. She didn't break her brother's heart, again, the opposite. But she was still happy to leave this town and start over again. She expected everything to be exactly like before that girl came to the town.
Except… Except it didn't.
Edward's state was probably the biggest shock. No matter how much Alice and Carlisle told her, Rosalie never believed that vampires could mate with humans. Alice thought of her hypocrite, reminding her the way she had found Emmett. But it was not the same! She carried Emmett home and begged Carlisle to change him because she felt that he had a potential. Something like an electric current twirling around him, she could feel it. Mate part came much later. Edward never thought that Bella had the potential to be with him forever, wasn't that the biggest proof that they were not mated? So she assumed that he would be just fine. He wasn't.
The second shock was that how much they got used to having her around. Even herself.
Esme still bought her favorite snacks during their necessary shopping trips to supermarkets. She remembers finding her crumpled in kitchen floor, sobbing tearlessly with realization that Isabella was not there to eat them now.
Carlisle still kept a big medical emergency kit in their garage, even though nobody needed it anymore. She saw him adding some new stuff there, after pretty much every shift he ended. He thought nobody saw him, she did.
Emmett… Emmett broke her heart. He was in denial, all the time. He insisted on changing the floormats when they were moving because they were "a death trap for Bella, she would trip and break her neck." Nobody had the heart to tell him no. He kept saying things like "Wait until Bella hears this!" She didn't know how to react to she just kept quiet.
Even her own routine was so carefully rounded about Isabella's school schedule, she was surprised to find herself feeling bored out of her mind on Friday evenings because that was the time she usually came to their house and Rosalie went hunting or worked in the garage to avoid her. It took some time to get used to the new "nothing to avoid" schedule.
She would never admit it out loud, but she was happy when she heard that they were going back. She missed the way her family was with Isabella, and if she was the key-Rosalie was willing to endure her until Edward gave up and changed her. But again, nothing was the same.
She would also never admit it but there was a gnawing feeling in her body, watching Alice try to pull her from the disassociation. The café meeting was horrible, Alice came home confused and hurt, telling the family how she stopped paying attention to her and how cold she became. Rosalie thought that it was the cold shoulder, until she saw her in the cafeteria the next day.
It was disassociation and her medical training gave big warning signs at the sight of Isabella in the following three days. Her mind jumping from schizophrenia to DID*, making Edward flinch.
The feeling was very unsettling. It made her worried. Surprisingly not only for the family but for the girl herself. There, she thought. I admit it. I'm worried for Isabella.
*DID: Dissociative identity disorder (DID) is a rare and complex psychological condition where a person experiences two or more distinct identities called 'alters'. It is usually a long-term condition that occurs in response to extreme trauma.