Hey Amanda,

First of all, congrats on your upcoming wedding. I know how busy you must be putting all of the little details together. haha I remember it all too well. 

As for the updo, well, I'm afraid that if you're going with a professional stylist and a professional style, there will be some inevitable professional damage.
    The reason that stylists backcomb, spray and fry your hair into "perfection" is because that is how they are trained to create a style. They take this to extreme levels if you have fine hair. This is because stylists don't care so much about the health of your hair as they do about the overall æsthetic.

Try talking things over with your stylist and express to her your concerns about damaging your healthy hair. She may be a little kinder to your hair or at least console you in some way.

Like you, I also did the tiara/veil/updo thing for my wedding. Shelled out $75 for an elaborate weave with the gratuitous little curly tendrils and enough hairpins to set off a metal detector. It was a lovely style, but it all ended up getting covered by my veil anyway. There was tons of backcombing, spraying, curling, drying, etc. involved, so naturally there was probably some damage to go along with it...though I didn't really pay attention to such things at the time. 

So my answer for whether all of that is worth it for just one day is...probably not. That is to say...I definitely wouldn't repeat the experience. But I also have the benefit of hindsight, which can change your perspective quite a bit.

What I can say is...go with your gut. Your choices have already been made, so if you truly want them, go for them and don't look back no matter how much damage results. Besides, if your hair is already healthy, then it should hold up to the stylist's torture fairly well. But definitely express your concerns to your stylist and see if there are any compromises or alternatives that can be made for the best interest of your hair.