Um don't you understand how humans develop? Their flaws are ingrained from the moment they experience things. The prince's flaws just grew more noticeable as time went on. Which brings us to the fact that claiming that he hasn't done the things he did to her in the past life, in this life, also misses the point in another way. He hasn't done these things to her because SHE has changed. Which, obviously, is just a stealthy way of victim blaming. Making it her fault that he did those things to her. Kthx.
I agree, I mean he did call for the royal doctor immediately when she broke down, even though he was already angry at her. I think they will have a good relationship this life. She changed and because of that, he changed too. At first she was cold and serious and that was mirrored by him. Now she's sweet and caring, so maybe he will be too? ╮( ̄▽ ̄)╭
But that's the point of story, even if it sucks. And in the end whether if it's victim blaming or not is depend on how the readers perceived it. Some people could be see it as she finally can rule her own life, she's the one who hold the steering wheel for her new future. If she should get away and live in blissful life next as paying for her past misfortune, she should be get a brand new life and reborn as different character. There's no way this story can avoided that "stealthly victim blaming" with this kind of plot.

Personally speaking I dont mind that Tia and the Prince end up together. This prince is different (still dickish) than the one from her past life. He still hasn't done anything wrong technically so I dont harbour any hatred for the guy. I think with this recent chapter even Tia has come to terms with that a little and I'm pretty sure she will come to think of this prince as a completely different person at some point.