problems after my engagement.

Your in-laws like you for who you are - why should they change their temperment/socializing to suit you? See your own comments above - they do a lot for you, but you don’t like that they’re not as social as your sister’s in-laws? That’s unfair to them - why should they change their demeanour so they can meet an arbitrary standard that your sister’s in-laws have set.

Remember to always be grateful for what Allah has blessed you (loving in-laws) with and to not express na-shukrapana.