My best friend has been having such a difficult time facing life.  She used to say that her guy was her “oxygen” and that she was not able to breathe or function unless he was with her. When he left her, she said that he took all of her heart with him.  She feels that he still loves her, and she wants to get her boyfriend back just desperately.  I have told her that one tip that I read online was for her to start trying to build a life totally separately from him.  He will see that she is happy and possibly be interested.