Propose to her
I made an account 10 years later, just to tell you how wrong you are. It's very clear by the end of the questline that she doesn't love Bassiano as much as she thought she did herself, and she quite literally has a nervous breakdown over not being able to marry nor see the milletian again, regardless of gender the text should be the same. Knowing nexon however, it was probably written with a male protag in mind, but that's what it is. No friend says "Was my feelings not clear to you?" While sobbing to you after their supposed happy marriage.