It happens without warning, and it devastates you: Your closest girlfriend cuts you off completely. No more late-night phone calls and emails, no more catch-up lunches and dinners. She has decided for whatever reason to move on with her life and has left you to try to make sense of what happened. The experience can be as painful as the death of a loved one and as confusing as an unexpected breakup with a significant other. You replay scenes from the friendship and wonder what you did wrong. You've lost a loved one...