Barbie... My only advise would be that if you don't want him back...stop trying to figure out his motivation (which I guess would be true even if you wanted him back)
His motivation might simply be to have a more positive relationship with his children. Maybe he realizes how much he messed up with them and is trying to reconnect.
His motivating factors do not concern you. I agree with you that divorce doesn't bring closure and I agree with the other poster who said that you are the one who brings closure. Closure also doesn't mean that you approve of what he's done. It means you approve of what you are doing...that you have let go of them and moved on to a place where you matter more.
