She was upset about her lover dying but she was upset for the cause he had died for. He wasn't fighting for Tyrion. He was fighting for Elia. She was angry that Oberyn couldn't take revenge after the mountain confessed. It proved that a Lannister was behind elia's murder. to add insult to injury her lover that fathered her children had died in the most traumatic way. #ellariasand #ellariasandmartell