roomie troubles

I have a problem. All right admittedly, I have more than one but this problem is tops on my list for this week. Before I begin I just have to say I am in love with the show new girl I absolutely L O V E it.  So, back to the problem. My beloved roomie Tree, wrecked her car. Now it was not her fault at all in fact she is lucky to make it out. However, now my car is the only vehicle or so it seems... My dad does not emphatically does not want her driving my car. She knows this and she continually relies on my need for acceptance and my continual reluctant doormat status to use it.  After she has seen me as an emotional wreck. I don't get it. I do not know what to do.