I believe my elder sister might be an abuser. What signs and…

Hi there,
Thank you for waiting.
I am sorry to hear about your older sister's situation.
It sounds like she has mood swings.
She may have mood disorder such as bipolar disorder and/or personality disorder such as Borderline personality disorder (BPD).
People with Bipolar disorder and/or BPD may exhibit such behavior.
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.
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.
People with Bipolar disorder and BPD may exhibit rage tantrums and can be abusive towards the other at times.
Yes, she can manage her symptoms and get better with treatment.
Your sister may need PSYCHOTHERAPY weekly - individual and group therapy. Cognitive-behavior therapy (CBT) or Psychodynamic therapy may be effective for her condition.
You may need help and support to associate with her. You may need to get support from a counselor, your family and friends who are also aware of your sister's problem. You may need to be patient with her behavior - angry outbursts and/or erratic behavior as he has this serious illness. However, set limits with her behavior without high emotion. You may not change yourself to accommodate her behavior as she may try to manipulate you. Keep an honest perspective, especially in regard to your own needs. Develop friendships and social interactions with other people, making sure you are not sacrificing your own quality of life in your efforts to deal with your sister.
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