I am so sorry this is happening to you. I thought perhaps you sister may have undergone some trauma or grew up with an upbringing where she was forced to play the caregiver role to an extreme or even just a personality glitch, but it seems like it may not be so. Unfortunately, you may need to cut ties or set firm boundaries with your sister. You have the ability to take care of yourself. You are capable of taking care of yourself. You do not need your sister to care for you. As for the car, it's illogical to buckle down on a car on the basis someone will die. That's not true. Do not allow your sister to blame you for the death of a love one over financial reasons. Give her a call and be honest. This is not your battle, it is hers and hers alone.