I don't like the mc, if you really want to be that cold leave the poor man alone.
Well, while she is the reincarnation of Martina (300+ y/o IF she was alive, which she isn't) she is NOT Martina. In this next life she is Astina who still has her memory as Martina.
She's 19, the duke's 26, not that much age difference so I wouldn't say she's too old. She's younger even though she seemed more experienced.
But she is so closed up that she doesn't want to give second chances, the duke can't approach her emotionally because she was betrayed by the previous king that resemblance the duke, that bothers me, if she can't see that they are to different individuals then bye bye. (I know the story is like this and in the end is gonna end well but it's irritating).
I'm team duke so I think he deserves better.
I find the mc a piece of shit (the other main characters too), the only character it's worth something is the officer.
(Just an opinion)