Isobel has been trying to keep herself together, but with the missing time in the real world, missing time in her dreams, killing Rosa in her dreams, she couldn't pretend she was fine anymore, so she hid. She had spent more time in her house than she had in a month. She even stop replying to text, emails, she was curled up on her couch, watching The Land Before Time. It was her feel good movie and she was trying to make herself feel good.
When she heard the knock, she sighed, but ignored it, but when she heard Max's voice, she paused the movie, looking at the hall that look at the foyer, tempted to text him to go away. However, being twins he answered her before she could even do it, that he wasn't leaving. So with a growl, she got him, wrapped her blanket around her and barefooted patted to the door.
After unlocking it, she opened it, turned around and walked back to her livingroom without even saying hello.