First and foremost, it is important you realize you cannot do his recovery for him. You cannot make the decision for him that he needs or wants recovery. It is a decision only he can make, and peer pressure, discussing, arguing or threatening won't help him make that decision. It is one he must reach at his own pace and with evidence acceptable to him that he cannot refute, ignore, hide from, deny or rationalize away.
Second, if and when he makes that decision, he must make it based on needing Christ and recovery for himself, not for you, his children, his family, his friends, his job, or anything else that can be held up to him as an important reason to embrace recovery. It must be for him and him alone, because it was him and him alone that turned his back on all those other things and embraced the drugs and/or alcohol as being more important that those things.
Finally, pray for him and love him unconditionally, but do nothing to protect him from the consequences of his actions. If he awakens too sick or wasted to go to work, don't call in for him to say he's "got the flu." Make him lie, don't become his liar for him. If he gets arrested for driving under the influence, leave him in jail. Don't bail him out, because he learns nothing by asking you protect to him. If he loses his license, his job, his car, etc., so be it. Don't take him to work, don't look the other way when he does something to "get around" his circumstances, and don't make excuses for him. He's a man, he's made the decision to use drugs and/or alcohol, so he's big enough to accept the consequences.
I will be praying for you to be able to stand up to your addict. It is a difficult road you turn on to, and it will perhaps be a long one. Holding him accountable doesn't make you a bad person, or someone who doesn't love him. Holding him accountable shows him the need to be responsible, or accept what happens when he isn't.
God bless and keep you both. Only Christ can deliver him from his addiction, and only Christ can deliver you from the pain of being married to his addiction. Hold fast!