Are my son and me better off living with my immature alcoholic little brother or my son's abusive father?

He is not hurting him or you physically or is abusive, so stay. However, DO try and explain to your child that adults sometimes choose bad words which should not be repeated and are not cool. Also try and talk to your bro and tell him you love it when he spends time with his nephew and you appreciate it but to please try and control his language a little more. Meanwhile, try and save up and find an apartment, maybe a low income one where you might have to put your name on a waiting list first or see if you qualify for section 8 housing.