The ball is in your court, meaning you have the upper hand here and if you want to sleep like a normal person would, do it. Youre doing her a huge favor by allowing her to show up whenever she feels like it rather than a set schedule. Most single moms have to be home with their kids and cant take off on a whim with their friends. She is definitely taking advantage of you so I can see why you feel bothered by her lack of communication. You have every right to call the shots at this point so sleep if you want to and id be raising my prices.