if the drinking problem has come to this extent that your marriage is at stake, u need to do something soon. there is no point in tryin to treat it without even him knowing about the treatment. unless he decides to quit, it cannot be made possible to do so. please convince him somehow & take him to a de-addiction centre & get him admitted for few days. he will need lot of counselling
& treatment therafter fo him to get out of it. its impossible for him to get out of it by him not willing for the same.