I am sorry to hear about your situation. She should not be on her own due to her age. If you are willing to care for her which you seem to be you can petition the court. Although her father and mother's boyfriend are interested, their motives have been questioned and yours have not so it appears that you are best suited for this.
You should contact an attorney to discuss your questions as additional information would be helpful.
Our firm has many years of experience in this field.
I wish you the best of luck.
Please remember that I do not normally monitor these questions after I have posted a reply.
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