First of all I would document what you have found with time stamped video or digital camera pics, as they will help you in court.
Next I have to ask, is this child your son or just "the boy"? IF in fact he is your son, then you will also want to file for temporary custody when you file for divorce so that your son is not left in the care of a cocaine user and alcoholic.
Document everything, and get you and your child out of there ASAP.
The disease of addiction, be it alcoholic, coke, crack, or all of that and more progresses and gets worse and worse. You already sense in your gut that she is 'gas lighting' you, so......................... the ball is in your court, what will you do next to protect that child and yourself?
J M H O
Love and hugs,