I second the drug test idea and the point that we lie. Just cover your butt and don't trust him for a long while. Especially if he's not seeking help. Try Al-anon meetings. They'll understand you.
its possible but unlikely. sorry. i am a recovering heroin and crack/cocaine user. i have stopped for a few weeks but never long enough to really really be considered clean. i dont know how long he was using, and if he is smoking he might not have as bad of withdraw as an IV Heroin user. i have been put out of my house and not allowed to see my daughter unless her mom was there and honestly, i still use once in a while. i just started intensive outpatient at a new place but these drugs are very very hard to get away from. buy a couple urine tests. you can get them at the drug store or order them online just type in drug tests in the search bar. i saw opiate tests for 3 dollars on one site. sad thing to say but dont trust him. we lie when we are using to save our *****. we would lie to jesus' face if it came down to it. i mean i am doing much better, gone from using three or four times a day to a few times a month, but its still using, and i still lie about it if it means my ***. he needs a program and help. dont let yourself and children be victims of an addict. honestly i dont deserve to be around my daughter and fiancee until i am REALLY clean. some people it is really hard to tell when they are using, nobody knew i was using and i was high all day every day. just drug test him, dont tell him your gonna do it and dont give him a choice or a chance to rig the test. hes your husband, you can watch him pee right. good luck and im very sorry. believe that he probably really loves you and the children though and doesnt want the life he is stuck in with the drugs. he may need help.