Eve I know several friends who love having their adult offspring at home, especially when they have lots of room like your folks. I think as long as everyone gets along well and respects boundaries it can be positive (intergenerational living projects are a an example of this).

Have everything crossed for you in your job search, I know how hard you have been working forward towards this.

In terms of your 'obsessing' about your ex, it may be that you are prone to rumination generally? (rather than OCD) This is a pattern I also struggle with, it can be very self destructive.