Cathy,
I have just rejoined this board after a long absence, and thought I would add my 2 cents if you don't mind. I feel so bad that you have to go through all this angst when you should be enjoying these months to the fullest. I am a wedding coordinator and event planner, and my advice would be two-fold:
1. Budget ...you mentioned that you gave your daughter a number that you were comfortable paying for the wedding. Stick to it, but let her decide how she wants to spend it. If she wants a huge shower or an expensive dress or a world famous photographer, so be it. It is her wedding, and she should be able to make those choices. However, if she "blows" it all on a shower, and doesn't have enough left for flowers or a fancy cake, or whatever, then she has made that choice. The budget should be completely flexible within its components, but the bottom line is the bottom line...no matter what. As an extra incentive, if there is any money left in the budget, you could offer that to your daughter as a cash payment when the wedding is over, to spend on her honeymoon, furniture, or anything else she would like. This forces her to make some big girl decisions as to what is really a priority to her for the wedding, and keeps you and your husband sane as well.

2. Wedding Planner. Most people think this is an extra expense, and when wedding costs are spiraling out of control, it is the last thing they want to add. However, I can assure you that if you can hire one, he or she will be well worth the cost. They can save you money in the long run by sometimes having access to vendors that offer discounts if they recommend them, they know which vendors offer more value for the money, they can go over contracts BEFORE you sign them to protect you from small print that could cost money. Most important, a good one is also used to many of the family dischord you have related and can be an unemotional third party that might just be able to offer compromises and cool things down when the different sides disagree. If nothing else, hiring a wedding planner for simply the Day of Event services can help immensely on the wedding day itself....especially with a wedding that needs the coordination of 11 bridesmaids!

Check out the Association of Bridal Consultants...www.bridalassn.com
for a consultant in your area. I guarantee there is someone with expertise in these matters that can help you.