My stepbrother's girlfriend took my car while I was sleeping and got into an accident.

I assume you have only liability coverage, not collision coverage. Liability coverage pays for medical bills and damage to other cars if you cause an accident. Collision coverage pays for repairs of your own car in case of an accident, and comprehensive coverage pays for damage caused to your car by something other than an accident, such as theft, vandalism or natural disasters.

Had you purchased collision coverage, the auto insurance company would compensate you for repairs or, if the vehicle was considered "totaled," tow the car to a salvage yard and offer you the cash value for it. When a vehicle is totaled, it means the repair costs have exceeded a certain threshold of the car's value, such as 70 percent.

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Since you don't have collision insurance, your best bet is to file a claim on your stepbrother's girlfriend's insurance. She should have liability insurance that would cover the damage she caused while driving your car.

If she has no car insurance, then you basically have three options. You could ask your stepbrother's girlfriend to pay up for the damage she caused. If she refuses, your next option is to sue her. Whether the results of a lawsuit will be worth the legal fees and drama involved with suing a relative's significant other is a serious question you'll have to consider. Finally, your last option is to pay for the repairs out of your own pocket or buy another car. Read more about what happens when a friend crashes your car.