Eating with those who are eating and drinking haram

I live in a foster family of non-muslims/ non-mahrams and they eat haram and drink haram and I am a Muslim and they let us eat halal. But there are my two sisters and brother there too. My question is if I sit with them and eat halal but they are eating haram and drinking haram (I am not eating haram), am I allowed to sit with them, is it haram or halal? I think that I have heard a hadith about sitting with those who wine is being served to. And if it is the case that I am not allowed to sit with them when they do that, does it apply to all haram meat (is there a hadith about sitting with those who are 'eating' haram)? And what should I do if they do not allow me to follow the rulings of Islam? Could you please quote some hadith with the exact source as well?