HI Toffee,
read your thread and trust me it really made me feel you pain. I really understand your position. And therefore am going to give you advice which may come out as harsh but I'm only being honest.
If a guy even before getting married to you is already threatening to call off teh wedding..you may wana rethink your decision to marry him. Time before the wedding is so sensitive that both guy and the girl and their respective families are extra cautious towards each other becasue any little mistunderstanding can lead towards disastrous results as time before the wedding is hectic for the families.
In your situation you have not even married the guy yet and he is already treating you the way you mentioend he was. Threatening to call off the wedding is the least responsible thing he can do. If he's threatening to call it off and treating you like this before the wedding ( when he should be scared of losing you because you can call off the wedding), you can judge how he would treat you after he's married to you.
I would strongly recommend you rethink your decision to marry him. I know you might probably think that you have invested 5 years in this relationship and as you mentioned really stood up to marry this guy and convinced your family for this guy. But you have to think can you spend your 50+ years of your life with him? with a guy who's giving you so much attitude and treating you like he does not care for you. He can play the same game with you for the rest of your life of caling/breaking the wedding off. You are lucky that you found out on time his real face. Take the right step. Pray to ALLAH to show you the right step and give you guidance as to what to do.
Your family will be very supportive if you decide to call off the wedding because of his behaviour but please dont take any steps or make decisions in a haste or under emotional pressure.