Are you both going to do suboxone ? doing this through a doctor/clinic , or off the streets? (not judging, just asking, my AS has done 'bout everything!)
From what you've said, you have a pretty good plan to detox, but fighting the cravings afterwards....I'm not sure people actually realize just how powerful these cravings can be. Thinking of and listing 'triggers' , things that you associate with using might also be a good idea . For my AS, his biggest trigger was always a paycheck (when he worked long enough to get one) or just cash. Money = drugs to him. Have you thought about hanging out with a different crowd of people, non-users, after you quit? A good place to meet some (might???) be at a place like NA. Just a thought. Keep us posted on your progress!