Hi there, Thank you for your reply.
I'm sorry to hear about your sister's situation. It sounds like she may have mood disorder and some neuro-psychiatric condition such as ADD and Bipolar disorder.
I wonder if she had a trauma in childhood.
Her lying and promiscuity in high school may have to do with ADD and impulse control problems. I suspect she may have Bipolar disorder or Borderline personality disorder (BPD) as she exhibits impulsive, extreme and risky sexual behaviors. It sounds like she is able to make friends, finish college, and ask others for help (e.g., attend a church suuport group).
However, she needs ongoing and intensive treatment (psychotherapy and medication assuming she has mood swings) for her condition.
According to your report, she is not suicidal. That's good. But, she can be harmful to self as she practices unsafe sex. If she is dangerous to self (and others) due to her condition, call a local mobile crisis team or psychiatric emergency response team designated by his city and county to initiate psychiatric assessment and involuntary hospitalization. Or, seek help immediately. Call 1-800-273-TALK (8255) to reach a 24 hour crisis center or dial 911 for immediate assistance. I understand she is refusing to see a doctor of any kind (her doctor, a psychiatrist and a psychologist) though you, her family, and friends have encouraged her to get treatment. If she is adult, she HAS TO ACCEPT WITH TREATMENT .
Let me explain her potential condition - Bipolar disorder causes mood swings that range from of the lows of depression to the highs of mania. When you become depressed, you may feel sad or hopeless and lose interest or pleasure in most activities. When your mood shifts in the other direction, you may feel euphoric and full of energy. Mood shifts may only occur only a few times a year, or as often as several times a day. It can cause symptoms of depression and mania at the same time.
Borderline Personality disorder (BPD) is emotional regulation problems. BPD is a pervasive pattern of instability in interpersonal relationships, self-image, affect, and marked impulsivity. A person with BPD is intensely fearful of abandonment and may engage in impulsive and extreme behaviors to keep other people with them. Disturbances in self-image are often manifested as frequent shifts in career goals and sexual identity, while impulsivity is reflected in unsafe sex practices, reckless driving, financial irresponsibility, and substance abuse.
In any case, she will need PSYCHOTHERAPY weekly - individual and group therapy. Cognitive-behavior therapy (CBT) or Psychodynamic therapy may be effective for her condition. CBT will work for addiction as well. If she has Bipolar disorder, she needs to work with a psychiatrist (M.D.) and a psychotherapist. Treatment consists of pharmacotherapy (by psychiatrist), individual psychotherapy (Cognitive-behavior therapy - CBT) or Interpersonal therapy (ITP) by a licensed psychologist or psychotherapist), and group therapy or support group by a psychotherapist.
I hope your sister accepts treatment as soon as possible.
Please feel free to ask me a question if you have even after you get this answer. All the best,