Tina couldn’t even remember the guy, let alone the incident, but it was the start of Rick’s paranoid fixation that she was coming on to every man she met.
-- Narrator (Part 1, Chapter 1)

Importance: Rick slapped Tina for the first time the night of their wedding because she danced with one of his colleagues from work. She indicates that after that Rick was paranoid that Tina was trying to attract other men even though she was married to him.

But Rick was a master manipulator of women, a skill he had learnt from a very early age, and Tina knew exactly who was to blame.
-- Narrator (Part 1, Chapter 3)

Importance: Because Rick’s mother had always allowed her son to get away with manipulating her, Tina blamed Molly for Rick’s ability to manipulate women. He used this ability to manipulate Tina even though she was aware of unique talent for manipulation.

You don’t get it, do...
-- Tina (Part 1, Chapter 3)