Hi Aussie,
Sorry to hear about your pain. It is unlikely that a die hard JW is ever going to be a good person to be married to, so it is probably worth thinking of breaking it off. Even if you were to convince him the WTS teaches untruths and he left he will have huge baggage at loosing family etc.
That said, you may as well try a few questions to see if you can get through to him. You need to take is slow and unemotional, maybe asking just one question a day. I find that an effective way to get through to JWs is to show that the Watchtower has made significant changes to doctrine, and then hide the truth about what they used to say.
Ask him why he feels he is so lucky to have been born into the one tiny religion that is going to be saved. Then mention that the Mormons think only they are the truth, how would he feel about a raised Mormon that believed they were the truth who would not research the history of their religion.
Once you have set the stage, then ask him some historical questions. Read him a quote such as Awake! 1973 January 22 p.8 “… Jehovah's witnesses pointed to the year 1914, decades in advance , as marking the start of "the conclusion of the system of things.” Then ask him if he knows what the Watchtower really said was going to happen in 1914 prior to that date, and if anything stated came true. There are a lot of quotes at http://www.jwfacts.com/index_files/1914dates.htm He is not going to trust anything from an "apostate" site so ask him to find the original publications and look it up himself. If he is prepared to preach to convert others, and wants to convert you the least he should do is know the truth about his religion.
Other interesting issues are blood transfusions. For 50 years they said that blood was ok. Then for 50 years they said nothing in blood can be used, no fractions. Now they say that blood fractions are ok. Who's fault is it that JWs died not having a blood fraction in the 70's when now they are allowed to have them. The same is true about organ transplants.
Another point to raise on a separate day is the word Jehovah. Does he know that YHWH never appeared in the New Testament and the Watchtower dishonestly includes it?
Hope that helps a bit.
There are lots of questions and quotes at jwfacts.com.