>>514197817
Pretty sure the term was applied here to imply that op is in a lower stage of development. Associative play is what toddlers learn after parallel play. The suggestion is that op should be engaged in the same activity as his gf. Obviously TV has no value as a shared activity. Op could read the book aloud to her, but op is probably reading something dry and uninteresting because modern fiction is intentionally written to be hostile towards men, much like modern nonfiction is hostile towards women.
Even though the premise is avoiding child like behaviors, classic fairy tales, folk tales, and children's biographies such as picrel are actually very good for a night time ritual for a couple, and seamlessly carries over once they have children. I usually advise people take turns reading, but women are insecure so you have to be careful. Picking a children's book with words she doesn't know might make her feel bad because it's clearly a children's book. Simply pronounce it for her if she encounters it, give a one word definition while implying it's just the old fashioned way of saying the one word definition you offered.
It feels silly but playing out a short exchange using stuffed animals or dolls is another fun way of bonding, but it's a bit riskier. Women live for the consensus filter and if the even remembers how to play with toys, most will feel uncomfortable, and feel uncomfortable that you're so much better at it than here. If you encounter this you may want to intellectualize it as a form of collaborative story telling. Just copy paste the justification the d&d nerds gave you when bullying them as a teen and it should get through to her.