Something big happened to you that changed your life and your needed lifestyle. He, on the other hand, might NOT be on probation and answerable to an officer and court. This big thing that required you to change your lifestyle? You two need talk about it, the ramifications of it, the need for the household to be totally clean of drugs and your need to be adamant that you not go to jail. Before that happened, back when you DID do drugs... you were fine with him. You married him. You dug him.
So now you don't. It's not that difficult. It's about choices. All its ish about how your family has higher values? Totally bs. None of that mattered to you at all while you were doing drugs.
It is very common for people who quit doing drugs to have to distance themselves from the people they used to do drugs with. You used to do drugs with your husband. You can't do drugs anymore. That's what this is about, isn't it?
So you explain WHY it's an ultimatum and you make it clear one or the other of you are moving out immediately unless the drugs are completely dismissed from your lives and make it true. Say it, mean it and he'll believe it.
Your marriage might be over. But it has nothing to do with your family having "higher values". This is between you and your husband and your necessary changes to your life.