How to kick my brother's gf from my house?

I live with my husband. A year back my brother started staying with us. We gave our spare room to him. He is neat and clean and all responsible. Issue started 2 months back, when he announced that his girlfriend got a job in our town and said she will stay with him in our house for couple of days. My husband and I were okay with this.

It has been a month and she is still living with us. I am an introvert and not so social person. After she started living with us, my brother stopped doing chores. Now his room is messy, and they don't clean the kitchen after using it. I used to cook my brother food. I still do that, but now the girl eats that food too, so now I have to cook more often. (I used to meal prep for a week. I cook separately for my brother as me and my husband are on a diet with different meal plan)

My brother doesn't pay for groceries or utilities because, hey he is my brother. But now it has spiked because there is his girlfriend as well. I don't want to pay for her expenses as well.

I want her out. My brother can move out with her if he wants. I want peace.

What do I do?