Honestly after 3 months of dating I’d not even want to meet any family members or them meeting mine, let alone having to try anything in particular with them.. But since you’ve already met her and have to continue meeting her probably more often than normal as she lives with him, I’d say you want to be polite and civil like you’d need to be with anyone. I don’t think anything else is required that early in the game

You don’t need to be trying anything more than that. Not after 3 months! You are still building relationship with him so there’s no need to be building anything with his family.

I don’t think there are any norms but I can assure that after 3 months of dating there are no expectations of any kind of trying anything beyond civility. As relationship develops and if it develops beyond dating and you know everyone better, then some things will develop naturally and some will require effort. It takes time

What do you mean by you being anti social? Like being quiet? Or something more obvious? Like she’d think you don’t like her?

As about your guy passing the negative or questionable messages about who said what about you, it’s a sure way to make you uncomfortable around these people. Does he in general run his mouth a lot? Just talks without thinking?

I think the fact that his daughter said something about you isn’t that big of a deal. I mean people say things. She doesn’t owe any loyalty to you yet as you don’t know each other. But your boyfriend shouldn’t be repeating things. I hope he was told in very specific terms to never do it again.

Relationships between adults and their parents’ partners are fragile enough and aren’t easy to build so no need to make it harder. But seriously I’d not hold it against her. People say things to their kids and parents but it just doesn’t need to repeated to the other person!

Other than that I think you should keep focusing on relationship with him and just be polite and civil with his family.