Good for you for setting out a plan.
It think it's imperative. Going to see the attorney, setting out your financial needs and goals (if required).
Practical items like who will live where. If your child is underage, what, ideally do you see for custody/visitation. Will you need something in place, like Soberlink to determine that he is sober each time visitation takes place.
You seem somewhat detached (which is normal), what are your fears about this. Do you still want to be in this marriage or is your concern more about the Son/Father relationship? If so, remember that with visitation only, he never (at least while he is underage) needs to see Dad drunk again, that's not a bad thing.