@ROOR21ROO
For political reasons, of course.
The union between two states that is formed with a marriage surpasses any bond that there is between individuals. . . "ubi major minor cessat".
As for Yurishen, even if she didn't have a lover at home, I'd still understand her. Leaving your whole life, your country and your culture behind is already difficult if you do it out of absolute conviction (like being in love or looking for your dream job); if you are forced like a chess pawn, even the most beautiful gold and marble castle and a queen's treatment is just a huge, horrible cage.