I hope this helps - is this for yourself or someone you know?
Is there professional psychological testing that can be done to get an official diagnosis?
How is Borderline Personality Disorder Diagnosed?
Personality disorders such as borderline personality disorder are typically diagnosed by a trained mental health professional, such as a psychologist or psychiatrist. Family physicians and general practitioners are generally not trained or well-equipped to make this type of psychological diagnosis. So while you can initially consult a family physician about this problem, they should refer you to a mental health professional for diagnosis and treatment. There are no laboratory, blood or genetic tests that are used to diagnose borderline personality disorder.
Many people with borderline personality disorder don’t seek out treatment. People with personality disorders, in general, do not often seek out treatment until the disorder starts to significantly interfere or otherwise impact a person’s life. This most often happens when a person’s coping resources are stretched too thin to deal with stress or other life events.
A diagnosis for borderline personality disorder is made by a mental health professional comparing your symptoms and life history with those listed here. They will make a determination whether your symptoms meet the criteria necessary for a personality disorder diagnosis. Borderline Personality Disorder | Psych Central
Treatment of borderline personality disorder typically involves long-term psychotherapy with a therapist that has experience in treating this kind of personality disorder. Medications may also be prescribed to help with specific troubling and debilitating symptoms. Borderline Personality Disorder Treatment | Psych Central