I think you are obsessing over him and it is not healthy. Even if he using, is it affecting you negatively? You cannot change him. It has to come from within. If he is a good husband and a father let him be. You have made your point. Remind him again when the time is right. You catch more flies with honey than with vinegar.
If he not mistreating you there is no cause to panic. Not all users are addicts just like not all heavy drinkers are alcoholics.