Bed sharing

Seeking advice. My son is BF and we've been cosleeping since the beginning. Started bed sharing at a month old out of desperation, lack of sleep was a major issue for me and learning to nurse laying down was a life saver. Now my son is 7 months + 1 week old. My husband hasn't been sleeping with us ( has been staying in the guest room ) because he is a heavy drinker and he smokes so due to safety guidelines I'm not comfortable with him being in bed with the baby. He is not willing to quit, or help commit to helping me with a different bedtime routine (other than cry it out), so it seems things will have to remain as is, because as hard as I try, my son will not sleep in his crib. I've tried heating it first, putting him in just before falling asleep, etc, but nothing has worked. My husband thinks I'm just "making up reasons to be worried" as far as safety / bed sharing goes as I know this is hurting our marriage, but because he's unwilling to change his habits I really don't know what to do? I'm against trying CIO but wondering if it makes sense to try it if this is going to hurt our marriage? I truly enjoy bed sharing with my son. In a tight spot with this situation....advice appreciated. Thank you in advance!