a lot of participations sent purchased dress and gifts received

Even the English Royal House was ready for anything, even a possible "no" of the bride. A rethinking at the last minute in front of the altar is certainly not a probable event, but one of his possibilities was foreseen. For this reason the British secret services had developed a plan ("Operation Pumpkin") ready in every detail, according to which dozens of men hidden in the crowd in front of Westminster were ready to form a cordon around the fleeing bride.
Apart from the borderline cases concerning VIP marriages, what happens in the world of ordinary mortals in the event that one of the spouses abandons the other at the altar at the time of the yes, or after organizing the wedding, with a lot of participations sent , purchased dress and gifts received?
The rules to follow imposed by the Galateo are these:

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- If the break does not take place at the last or at the time of the "yes" at the altar, the communication of the break must be made immediately to the guests
- Gifts received from guests must be returned from the first to the last
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- the expenses incurred up to that moment for the wedding, from the organization of the reception to the payment of the honeymoon to all the rest, must be compensated by the groom who has changed his mind

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It is not only the etiquette that prescribes the actions to be taken once the promise of marriage is broken: in fact, the abandoned can sue the former promised spouse and demand compensation for moral damages.
In this regard, a ruling by the Civil Cassation, section III , n. 9052/2010, reads: "The promise of marriage obliges the promising party who, without due cause, refuses to perform it to compensate for the damage caused to the other party ...".