In most states, the insurance follows the car. This means that if your car was involved in an accident, your insurance is resposible for the damages to another party's car and their injuries if any.
Hopefully, you did not knowlingly allow your car to be used by an unlicensed driver. Each insurance company has their own rules, regulations about allowing an unlicensed driver to use the car.
If your insurance company denies coverage if you knowingly allowed the unlicensed driver to use your car, then you could be held legally liable for any damages or injuries. If that is the case you could have a judgement made against you for such damages or injuries. Your insurance company may not be responsible to defend your or to offer any legal assistance if the accident is not covered by your policy, since the driver was not a licensed driver.