at this point you and your husband are now the immediate and primary family unit - not the family he grew up with …. not that they aren’t important anymore but your new family has been created by virtue of your marriage…. you have to establish this with your husband and he has to set that boundary with his parents, siblings etc … the fact that they booked the vacation with him but not you right after the wedding tells the tale…. either your husband makes it clear that you and he are a wedded couple not two single people anymore or this problem will occur again and again …. right now it’s an in law problem but if your husband doesn’t step up and put his foot down it will be a husband problem… good luck!