Chelsea and Nick broke up a few weeks ago. Chelsea developed feelings for Dr. Daniel Jonas - the doc who performed the pancreas operation on Chelsea to save Bo's life and he also saved Chelsea's life after she got an infection due to the operation. Chelsea told Nick that her feelings for him changed and she thought it would be better for Nick to let him go - although she still wanted to be friends with him. Nick guessed that Chelsea had feelings for Daniel even though she did not say it to Nick directly. Nick threw himself into his work as a teacher and he also worked on his enviromental grant project. Chelsea admitted to Daniel that she had feelings for him but he has been resistant to starting a relationship with her for various reasons. Chelsea and Nick reestablished their friendship recently. Hope that helps to answer your question.
