Tired and alone..

I am so fed up with my living situation. I live with my mom and her grown ass son is always coming to my house and smoking weed in here like if im not pregnant. I used to smoke before finding out i was pregnant and have nothing against it but when you are doing it around me and my baby thats when it upsets me and the fact that my mom never tells him anything. Hes like the golden child to her. I was never allowed to smoke at home so i would have to hide it from her but him he even does it while im pregnant and she has no care in the world. I am worried about bringing my newborn home and having to deal with this. I dont understand why he cant just go outside or something like my house ia not that big and the smoke literally stays trapped. Im so sad and idk what ima do because i try and explain to my mom thats not healty for me and baby even my obgyn has told me to not smoke and the harms it can cause to my baby. I feel so uncomfortable and disrespected and i have no support whatsoever. Im so angry and have lost my respect for my family...