New to the blog, so frustrated don't know what to do...

I have a SD who is 20, decided to move out of her mother's home and get an apartment with a roommate for to go to school. She moved out 2 months prior to school starting, quit her job and expects that my husband pay for her rent until she finds another job and gets her grant money. This decision was the SD and the mother's. They came to my husband to ask for deposit and first months rent. SD dis not have a bed, so my husband goes out and buys her a brand new bedroom set (queen sized bed). Did this all behind my back. Since the SD moved closer to us, my husband gave her a key. She has came over on 2 separate occassions when we were not at home. First time I came home to find my computer room in disaray, second time I came home to find my clean folded clothes on the floor. When I mentioned it to my husband and told him if she comes over that she needs to pick up after herself, leave the house like she left it before she came over. he tells me that I should be the one to tell her. I told him he does because it will come out better coming from him since our relationship has just come to a "good place." So what does he do? He throws me under the bus right in front of her and makes a big deal out of it by saying "tell her, tell her" and I told him no, you tell her. So he finally tells her and her response was she wanted to watch tv on the couch and forgot the clothes on the floor. So come to find out that day she came over she came over to ask "Daddy for her 2nd month's rent. Her dad told her he didn't have it. So I get a text message that evening saying "It's obvious you don't want my dad helping me" I hope I get this job so I don't have to ask you for anything else." My husband just went back to work after being laid off for almost 2 months. I work and have been carrying the household bills and have fallen behind on some. How dare SD and her mother make decisions and expect that "Daddy" is going to bail them out. I am ALWAYS the blame when he tells her NO. Anything she wants, she gets, doesn't matter that we are behind in our household bills. I am SOOOOO frustrated because I have had to deal with BM dram and SD disrepecting me over the years, that I am so ready to leave. Any advice out there?