I think it is safe to say we all have "difficult" friends, but I bet you didn't know just how bad they can be for your health! [1] According to a study preformed by psychologists at Brigham Young University [2], simply being in the presence of someone you have a love/hate relationship with will not only elevate your heart rate and blood pressure, but they will generally leave you on edge.
Since it is inevitable that we have more than a handful of "ambivalent" friends, cutting all of them out of your life probably is easier said than done, but what I want to know is, have you ever broken up with a platonic friend [2] before? Have you ever felt the need to distance yourself from unpredictable or unreliable friends?
Source [3]