Friends car engine died when she let me drive it?

[psycho_0924]

About a week ago, I let my friend drive my car with myself in the passenger seat as she let me drive her car after with herself in her passenger seat. About 3 minutes into driving her car, her car stalled in the middle of the road and we were forced to push it to the side, with the help of friendly people nearby. We called AAA, which towed the car to her residence and it turns out that the engine is completely broken. I don't know what exactly is broken about it, as I dont know much about cars but now she wants me to pay $2,800 for a new engine and labor costs. I am a 18 year old, full-time University student that works part-time earning minimum wage, and feeling somewhat responsible for what happened that night, I told her that i can only afford to pay her about $100 a month. I know that seems like nothing, but as a college student, I have tons of expenses and that is what i am left over with at the end of the month. She argued that that is not enough and now she wants to take me to court. She says she will be suing me for 'Grand Theft Auto' and 'Vandalism'. I am doing my research to defend myself but I need help. What can I do? What can I say? How can I defend myself? Was it her fault for letting me drive her car? If anyone can help me, I would really appreciate it.