Most auto policies cover permissive users, so if you had the owner's permission to use the car, the policy on the car should cover you. If your friend will not give you the insurance info, you (or an investigator or attorney) may be able to get that from the DMV. If you are covered, the insurer will have a duty to defend, and they'll hire an attorney if the case gets filed.
If you were driving the vehicle with your friend in the car, then his insurance will cover the damages. Your parents should forward the paperwork they have received to your friend's insurance and let that insurance take care of it. Your friend may not appreciate you doing this--but if you did not have insurance, there is simply not much you can do. Unless you want to take care of the damages yourself-which make no sense.
Call the attorneys who have sent you the letter, tell them you are in the military, tell them you do not have insurance, tell then you were driving your friends vehicle, tell then your friend was in the car with you at the time of the accident. Wasn't there a police report made? If so, the insurance information should already be reflected in the police report.
I hope this helps-
If you had permission from the owner to use the car, you are what is known as a "permissive user". Under most insurance policies you will be covered. You need to be sure to forward the letter to your friend's insurance company as soon as possible.
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