I've been here in this same situation, I have an adult stepdaughter with five kids, and she's not even 30 yet, none of the dads have anything to do with the kids, and she also wont grow up, now the other grandma has two of them, and three are in foster care and she's about to lose them. They all lived here for a while and in addition to that my stepson and his two kids, so we had her,her five kids, her worthless only husband she had for a little while, stepson and two kids, and step sons girlfriend all in a three bedroom house with one tiny bathroom, we are pretty much financially ruined from the situation, but at least they are all gone, the only reason I let them stay here at all, was because the kids had no choice in the matter, There has to be a time when you say enough is enough, it sounds mean, but you also have the right to live, she is living off of you because she can. Set rules, and if she doesn't follow them, tell her to go, dont end up in the situation I did, you are not being unfair by setting rules and expectations of her, after all you are supporting her, and it's your house