Never, ever get in a car with a drunk driver. EVER.
Its understandable that you did your best to get her to quit biting you. However, if police had been present the reality is you would have probably both been arrested for DV. A lot of times they don't care who, what, or when, and leave it to the Court to decide who was wrong. An expensive, and stressful process with no guarantee you would be found innocent.
You got some serious issues going on here. I don't care how wonderful she is her behavior when she over indulges is scary. I will never understand why a raging drunk would grab keys, and insist on driving when there is a sober person available. WHY??? More importantly look at your own behavior here why in God's name would you get in a car with a person who was that drunk? Please don't do it again. My advice would be to walk away from this mess but you most likely aren't in that mind set yet. I advise a boundary that you not be around her when she is drinking like this ever.