You can't CONTROL it.
Keeping the money, filling up the gas tanks and buying cigs, packing his lunch. ... you are falling into the trap we all fall into. You are trying to control the addiction.
You can control yourself. Try to take afirmative action.
I start by setting my priorities, my kids come first. In order to take care of my kids, I have to take care of myself. When I am not at home the kids are at daycare, even if AH is available to watch them. i told him he can't stay calm and I won't leave the kids with him. That's it, suck it up.
I don't know though how wwell that would go over when your A is in recovery, and you suspect them of using. All I can say is your kids should be priority #1, not his feelings. If you send them to a sitter, send them for a sleepover etc. and he is insulted, oh well. If you leave them at home and he uses and something happens. ... . that will be worse than him being insulted.