smoking while pregnant

I'm 22 weeks, and I've never been a smoker. I'm living with my parents and sister and they all smoke. It's never bothered me before I got pregnant but now everytime I smell the cigarette smoke it gives me a major headache that I can't get rid of for hours and I hate having to stay in my room constantly when I'm at home just to avoid headaches. They get mad at me bc I don't want to sit in the living room with them and I've tried explaining to them that the cigarette smoke bothers me. My dad just tells me to get over it, and my mom says she'll quit smoking in the house when the baby gets here but I'm not sure it's not good for the baby when I have to smell it and sit with a migraine all day bc of it. I know it's their house and I should grateful but it just bothers me that they don't care about this but then complain when I stay in my room all day bc the rest of the house smells like cigarettes.