bf is OBSESSED with his family

This may be me being melodramatic but my boyfriend ALWAYS wants to spend time with his family instead of just me and him !!!
I only see him on the weekends cause he has things to do all week so when I see him I want it to just be us but everyweekend got the past month, both Saturday and Sunday we have done stuff with his brother and his friends ! 
Like tonight we were meant to be going out for a meal and he just text me there and said nah change of plans we are going to the cinema to see the movie we seen with his brother last weekend !!!!
I've explained to him before that I feel uncomfortable and out of place considering everyone there is 4+ years older than me but he doesn't listen and last time it caused a huge argument :( I don't know what to do cause it's making me so unhappy but he will end up going in a mood and I don't want that either 😔 help me out xx