My bf (21y/o) of 1y6m is almost always blowing me off for another family, that their family is close to. He had a thing for the youngest daughter (she has a bf) in the past. He says he’s only really close to her brother in law since her sister and kids live with them altogether. He says they’re both into the same trucks & share each others ideas. For example, today he interrupted me as he was on his phone watching their story saying “how do you go to monster truck show, and football game in same day?” He was so amused, he gets very amused around them, to the point that he doesn’t care if I’m there or not. Sometimes he’ll be over their family house & take a while to respond, but he says it’s because they look at their trucks outside. Also, another time we arrived at their son’s football game when it ended unintentionally. He quickly got out (he usually opens the door for me) he left me there for about 20mins with no remorse. He was so amused and excited just like a little kid with cake.

Should I say something? Am I overthinking or should I take it as a red flag??