I am sorry it has descended into something which has upset you vampirequeen and I hope you can arrive at a solution which pleases you all (although not holding my breath)
Just one contribution from me, when DD1 got married, Paw had been forced to give up work because of urgent bowel surgery and Lymphoma. He had no income or sick pay (as a contractor) and was not old enough to claim any sort of pension . We would dearly have loved to make a contribution to the wedding, the flowers perhaps, but DD and SIL to be were much better off than either set of parents so we and the in laws gave a token present. They bought them a big barbecue, we bought a teak bench. It was the gesture. At DD2's wedding the cake was a gift from her sister, this time we were in a position to offer to pay for the wine (they did a trip to France to keep costs down) At DD3's wedding, the photography was a gift from a friend, the flowers (done at cost) a gift from another. I bought the bride's shoes!
The old days of massive financial input from parents are an anachronism. I am so sorry the bride is taking this attitude, as a wedding should be about relationships not a mercenary business. She is jolly lucky that you are making such an effort to handle the issue so sensitively.