Jace regretted treating his wife the way he did with her at his grandfather's birthday party. That was the same girl that put her life at risk to save him. She only wanted to treat his wound but he shouted at her and said hurtful words to her. He never wanted to shout at her, he was just burning in anger at that moment.
And he was such a coward. He stayed away from home for three weeks instead of going home and asking her for forgiveness because she deserves it. But his pride wouldn't let him. Instead he stayed in his beach house.
What Kevin said that day was...