First welcome and my heart goes out to you and to your family. That said, I don't agree with you holding your mother hostage to keep her sober. It may seem like an act of love and support but it is demeaning. Your mother is an adult and she has the right to do whatever she chooses to do. Treating her like a a child and doing for her what she should be doing for herself is prolonging the problem.
It is said that we can be part of the problem or part of the solution. A big part of what gets a drunk sober is facing the consequences of their actions. A big part of what keeps them drinking is us...keeping them from getting too uncomfortable. Waking up in your own vomit a few to many times can do that for some and for others it takes much more.
What you should be doing is taking care of yourself, going to school and then to college and getting on with your life. This is not your burdon..it is your mothers. These are things that are important for you to grasp....before you end up taking the keys from your husband.
(((((Hugs))))
JT