We understand you want to know who is at fault so that you can move on and get treatment for your injuries. The good news, unless you did something to intentionally cause the accident, you are likely not going to be the one on the hook for it. There are usually going to be three parties who could be responsible for the accident:
The driver of your car. The truth is, if you were driving with a friend or a loved one, it can be really uncomfortable if you believe they were responsible for the accident you were in. However, you should speak with your lawyer if you suspect that your loved one was the cause and file a claim against their insurance. A personal relationship should not get in the way of you getting help.
The driver of the other car. If you suspect the other driver was responsible for the car accident, you and the driver of your car may both be filing claims against them.