Girlfriends family members trying to move into house

Me (18) and my girlfriend (19) live in a 2Br 2Bth Apartment. We have been living here for about 8 months. We both have good stable jobs and carry our weight equally and successfully. The reason we moved out so young is because my girlfriend lived in a very crowded house and did not feel wanted in her household. She babysat kids, Dogs and Cleaned her entire house and they made her feel horribly. So i strived to get a place early so she can feel more wanted and appreciated in her household. Me and my girlfriend never have an issue with splitting up bills, rent and costs. I cover ALL rent costs including Rent, Water, Gas and Electricity. She pays for WIFI and phone bills and mostly pays for groceries (The rest of her money is for her to spend on whatever she likes) Anyways For the 8 months we’ve lived here We’ve never had an issue at all, No major arguments or conflict. It’s perfect. I love it here with her. Until…

My girlfriend has a LOT of cousins and siblings living with her. They are deadbeats. they live in the Basement of her older sisters home, no Diploma, No job, No ged no plan to support themselves Just sit around gaming On the VR and sleeping all day eating all the snacks for her sisters children. (Mainly her brothers) (22YRO and 25YRO)

Basically both of her brothers were recently kicked to the curb by her sister and they’re BEGGING to move into our spot for just a week until they “get back on their feet” but they literally have no WAY to get back on their feet. I know this will go from One week, to 3 week to months.

My Girlfriend is very scared of “hurting peoples feelings”, “Letting people down” and “Saying No” We have been arguing about letting them come stay

My argument is basically: NO, I do not want your brothers here because i know for a fact they’ll overextend their stay and end up eating all of our stuff and just loathing around doing nothing. I also know that if they decide to stay, They will not leave when asks. They are that type of person. It will get physical and violent and I’ll be forced to physically removing them from our house.

Her argument is: Yes, They are my family, Regardless of them not having any plan to support themselves. My brother (22) Has autism and learning disabilities and it was not his fault he could not graduate. It’s only for a week until they find jobs and get off their feet.

What do I do? Here’s the message that I sent her today before sending this here.