I’m also a bit lost on why they lost, but I think the uncle took advantage of his marriage to the aunt to gain more authority in order to voice against the nephew’s marriage (uncle doesn’t want nephew to get married).
Regarding the funeral, the royal wedding happened a few days after the nephew returned to the palace (the detail where nephew got sick a few days right after his trip but got better right in time to join the wedding). I guess the timing between the aunt faking her death & the rotal wedding isn’t too far off. Also, in some Asian countries, apart from holding the actual funeral ceremony, usually the deceased’s spouse would be in a “grieving period” post-funeral (still dressed in funeral attire), could be for a few days/weeks or longer depends on each country’s customs.
The dialogues are so confusing. Or maybe I'm just dumb. But why the fuck did those two fight in chap 11? And the time line is also confusing. I'm assuming they were wearing white clothes on the aunts fake funeral but didn't she pass before the crown princes wedding? And according to the previous chapters, getting to where the uncle was would take about a week (or longer) so why was the funeral held so late?