You could find a job and work and seek treatment as well. Do you have a relative to live with? A friend to stay with provided you chip in for rent? Be creative. Or stay out of the house as much as possible - it worked for my friend.
You're admittedly in a very difficult situation and you shouldn't have to be making this decision. I'm sorry. Like others said Bs or Cs won't be enough. But if you want to be a doctor, and there may be other careers, you have to get better so that you can perform. Doing so might take some maneuvering or sacrifices.
