This probably wouldn't be ideal for an engaged couple.
If you really don’t want the bracelet anymore, you can go to the Sim you exchanged bracelets with and demand your Sims 4 friendship bracelet back. This is a Mean interaction, under the Malicious sub-category. This interaction removes the friendship bracelet from both Sims but it also damages the relationship and causes a Hurt sentiment. Also, this interaction destroys both bracelets in the inventory so they can’t be exchanged with someone else.
https://simscommunity.info/2023/05/16/the-sims-4-friendship-bracelets/