She did but you saw what the green boy felt... like maybe alll of that was just a bad dream .. so she is afraid that everyone will think of it that way cus she is still a child
What? She told him everything starting from her downfall to going back in time, something she didn't even tell her papa. I am talking about lying her way out of it. Remember the time when she went to the temple to get some answers and the god Vita told her about the screw up and gave Tia the power to carve her own path(Ch9,10)? A new oracle was sent by the god related to that. Tia should have taken advantage of this and tell everyone that the god besides giving her a new name also clarified(to Tia personally) that she isn't the girl they are looking for.
Or just tell everyone that she still wets her bed or something to get the engagement annulled ╮(￣▽￣)╭
Can't Tia just say that the goddess told her that the girl they are looking for (according to the prophecy) will appear in a few years and she is not the one? Marrying her would in fact start the apocalypse ? Can't she just live in peace without the king or the prince interfering in her life?