She was never too tired
She never cared if he played video games.
She never told Mantti’s embarassing secrets to her friends.
She never wanted Manti to “share his feelings” with her.
She never took over a drawer or his medicine cabinet.
She never flirted with other guys to make him jealous.
She never complained when his buddies came over to watch the game.
She never tried to read his text messages when he wasn’t around
She never complained about Manti looking at other girls
She never dragged him to a chick flick
I’m sure there are a lot of other reasons, too – add your ideas to the comments.