A: That "tradition" of the bride's family footing the whole wedding bill has pretty much passed. So first, give your parents a really big hug for paying for the whole shindig. Now, how to handle your future mother-in-law: She is being unreasonable and needs to be told that, but to protect your relationship with her, your fiancé should do the talking. He should express support for what your parents are doing and explain that the guest list is equally split between the two families. Hopefully that will be enough to get her to trim her list. If not, your parents, working with your fiancé, have a right to whittle down her guest list themselves. Another option is for your fiancé to go to his mother with the reception's per-person cost (including tax and gratuity). Then she can decide how important it is to her to invite the extra guests and write a check (before the wedding) to cover those costs.