Luke was stunned when he heard Elena's statement. Luke was also young when he found out his parent's relationship was fake.
His parent's marriage was not fake, but they acted harmoniously in front of Luke while they didn't love each other at that time.
Luke couldn't believe that they dared to deceive him like that, and they still tried to compensate him for their mistake after their reconciliation.
Luke was still lucky that Dad finally realized his feelings for Mom, and it took a while before his Mom could forgive him after she punished his Dad severely.
Dad needed to sleep outside for almost a year before he could move into the same room with Mom. Luke didn't help him to reduce his punishment because he deserved it.
But Luke never thought that Elena had a worse experience than him. It was not easy for a five years old girl to face this cruel reality.