Hi there! I think making a list of your values could be helpful. For example if you value a good nights sleep when you have to get up the next morning early for class then staying at your boyfriends house because your OCD thoughts want you to goes against your values and you then would do ERP and go home instead of staying. Also do ERP with the "I'm losing intrest in my boyfriend" possibly doing a written script with this and reading it over and over for about 10 minutes. or trying the downward arrow I am losing interest in my boyfriend How will that make him feel he will feel hurt does that make me a bad person I am a bad person... This is just an example at how you can take an idea and go to the extreme with it to help find out what your actual fear is.
Thank you!!