Timothy was not oblivious to what his father had done to his mother. His father was one of the reasons for his mother's nightmares and anxiety. But that was because he didn't know his mother's situation at that time.
What his father did to his mother was hard to forgive but his mother did. Maybe because she really does love his father that much. And Timothy was glad that she did because he doubts if he would ever see his mother as happy as she is right now without his father.
"Is there someone you can't get out of your head?" Diana suddenly asked which made Timothy taken aback. But Timothy cannot bring himself to lie to his mother, so he said, "Yes,"
"May I know who?" Diana was not certain if Timothy would answer her question. There was a great possibility that he would not answer her question but she still asked.