You should consult with an attorney in Georgia where you live. No doubt you can find a personal injury attorney who offers free consultations. You should rely on advice from individuals in your jurisdiction as the law differs from state to state.
Even if your friend turns the claim into her insurance company, there is still the possibility that the insurance company will pay her claim for the car; drop her as an insured; and sue you for the damage you caused. Not sure how far the random guy portion of your story is going to get you.
If you are sued by your friend, or her insurance company, a judgment stemming from a motor vehicle accident can affect your right to a driver's license. Best advice -- call a GA attorney.
NEVER listen to someone who says "don't call my insurer." Call them, since they may actually pay the claim. As a general rule your "friend" (and I use the term loosely) will not be able to sue you when the insurance is handling it (although it is possible you might be sued by the insurer, or sued by her for the deductible).
(A note: you have posted this question over and over. Once is plenty).
Even if she reports it to her insurance company, there is some potential for you to have to pay for the damages if you were found at fault. However, if the accident was caused by the person who got in the car that night, you would not have to pay. You were not clear in your question on what caused the accident itself. In the end, it is more a practical issue. If you do not have the funds to pay and she wants her car fixed, she will have to report it to her insurance company, which is her responsibility to do in any event. Also, she would not likely find an attorney to sue you, although she could file a claim in small claims court.
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