Afer declaring war, she takes Relena to her fortress which she believes is impenetrable. While the gundams fight outside, she and her grandfather keep egging Relena on in order to try and get her to tell the citizen of Brussels (the place that they're attacking) to give up. When Heero blasts through the fortress, Dekim calls Mariemaia to his side and, in a trance-like state, she goes to do just that. She doesn't get far, though, because, Relena slaps her before she can reach her grandfather. After this, as well as a short speech from Relena, she begins to realize that she was wrong all along. When Dekim goes to shoot Relena, Mariemaia jumps in front of her and takes the bullet, admitting that she was indeed wrong about everything. When Heero shows up, Mariemaia asks him to relieve her of her pain...so he pulls the trigger of an unloaded gun, symbolizing the death of the old Mariemaia and birth of a new, more understanding one. In honor of Treize, Lady Une adopts Mariemaia as her own and they visit his grave together.
I guess it's time for the DANDIN MATRIX RATING SCALE