Severe Fear Of Flying! Need Advice!

[soon2bmrsg16]

I have never flown before. I have always been scared of heights. Even as a child, when I would swing, I would get light-headed. Even the thought of flying has me nervous. Have you ever seen that episode of The Simpson's, when Marge is getting ready to fly and she says let me off the plane as it starts to taxi, then all of a sudden she jumps up and repeats let me off let me off let me off? Yeah, I feel like that times 10! My heart starts to race, I feel faint. I have tried figuring out where the fear came from, but I've never had any aviation related accidents either with myself or close relative. I really want to get over my fear. My fiancee will be flying first class (his choice not mine... he feels I will be more comfortable there) and I don't want to ruin our trip- let alone prevent the plane from taking off. I have hidden my fear from the kids so as not to make them anxious. I am at a loss. I am a therapist so I did the usual phobia related steps to address it, but I still feel terrified. Any advice?