How long has he been able to "pull off" this "Hey, I'm trying" thing in the past?
I normally recommend a 6-month period of separate residences, dating each other exclusively, before a wayward spouse is allowed to move back in -- ESPECIALLY when there are kids involved. However, considering your husband's lack of stick-tuitiveness for things like this, I'd probably shorten that, while still making him WORK for this.
