Both of you need immediate counseling. The thing about your mother is that, we don’t know what is the cause for this behavior. It is possible for you to grow up OK in this situation but experience would indicate future problems because you are living a continual traumatic life.
Perhaps the police is too harsh but the point is, that you should not have to live like this, and all options have to be considered. I have family members who because the parents refused to consider an alternative because of so called religious considerations, nothing good came of their Mehalach.
I do not think that the methods of taking your time to slowly and methodically analyze and consider this, is the best approach. If you could hear in your words your acceptance of this abuse, you would recoil in horror. It seems you are living in existential fear at every moment. This is utter abuse and
quite frankly, your mother’s behavior whatever excuse you can think of including drug addiction, is inhumane, off the charts, and she deserves nothing from you other than you committing her to full psychiatric and medical evaluation, however in your writing, you seem to shrug all this off, so that would be your starting point. I don’t know. If you want to suffer, then wait and suffer. But you don’t have to according to every moral position in the world.