I have to respond though to those who imply that this is all just a "diffence of religious beliefs" and that if there is truly love that it can survive. That may be true to a point, but I feel it would run much much deeper than that.
I basically say that in order to point to the deeper aspect, not to imply beliefs are all that's involved. The thing is when discussions of a religious nature comes up there is a tendancy for people to only focus on the arguments surrounding those beliefs, in other words we can get so caught up in debate over these beliefs that we forget to connect, even if it's our loved ones. Why else would religion break up marriages and families?
How significant the beliefs are depends on how serious people take it, so yes it can run very deep, whereas you might even have some active JWs who do not take it that seriously and they wouldn't have much issue over it. Beliefs in themselves are nothing, you can write them down on paper, but when people start to act on it they can go so far as to exclude their loved ones.
So in a way I am saying to focus on those more important things rather than the beliefs. You might deal with the beliefs and discuss them, but that in itself is strictly an intellectual process and doesn't go very deep. You stand a much better chance if you work from a deeper level. You can say the exact same thing verbally, but if it is said from the heart it has a better chance of reaching him. He may be on sort of an ego trip over the JW headship teaching, but if he has the family's best interest at heart he will notice and get angry about those things.
If anything don't forget to connect, and since beliefs are the point of contention right now it may be challenging, so don't forget to connect at other times in the day in everything else you do together. The thing is, people think if they get the beliefs worked out then there will be peace and harmony - wrong. If you ask me any issues over belief will naturally be worked out if you connect and establish the peace and harmony. (I remember the fruitage of the spirit, I don't remember fruitage of beliefs) Religious discussions may be a part of that process, on the surface, but it comes from a deeper connection. Some people even have different beliefs and they live together just fine, simply because there isn't any crazy fanaticism. Frankly what it comes down to is a person loves the idea they believe in rather than their mate who is real and standing right in front of them. So instead of getting into their head with them I'm saying shake them a little and snap them out of it! They cannot touch a belief and hold and embrace it, and it doesn't hug them back.
Don't be afraid of the JW influence, they only have so much time and exposure to your husband. If you connect the rest of the time in every aspect of life, then they don't stand a chance. It doesn't sound like he's all gone, there's hope. Yes there are people who lose their mate to the Watchtower, but there are also people the Watchtower lose to their loved ones - or ones that never really get in there.