What do I do?


I swear my life sounds like a t.v. show everytime I type it out. Essentially my Fiance whom I'm marrying August 9th has a sister she's 17. She has been in the last 5 years gotten in all kinds of trouble on probation, done very hardcore drugs never comes home and when she does is a menice. Well we went to his parents house to discuss wedding details and our guest list as his mom believes that all things should go through her. She was going to help pay for a portion of the wedding so Imade myself give wiggle room and listen. Anyways we got there when they werent home quite yet. We walked into the house in which his 17 yr. Old sister is running around naked. We immidiatly turned around and decided to call his mom and ask where they were. They said they'd be there in 10 min. So we went back in and sat down she came back out dressed thankfully and started whiningthat she needed tampons very badly and she was bleeding everywhere. I as a girl sympathized and told my fiance to take her to get some feminin hygene products and I'd wait there for when they got back. So they left or so I thought. She came running back into the house apparently she had told my fiance she forgot her money. When she came back in I asked if she was alright and she started screaming at me about how her boyfriend Luke (whom is wonderful) wont have sex with her yet because she easily becomes addicted to things and he wants to help her right herself and come off of drugs. He wants her to go back for her dimploma and then when she is in a better place explore sexual things as he feels that it needs to be based on love but healthy love. As she continues to scream i think she's venting. Suddenly she starts screaming Abel and runs out of the house. This young guy about her age comes running down the hall. Immidiatly I catch on and start yelling at him that there are little kids that live here and this is not her home before i can compose myself he turns around and punches me square in the face. I'm very clearly shaked and stunned. Well my fiance was in the car and seen him run out he didnt put two and two together. Apparently his parents drove up and she sats to him well mom and dad are here so mom can give me tampons. And runs back in the house where I still am. She starts yelling that I can't tell anyone because she loves Luke and also she'll get in trouble for having a guy in the house. While shes screaming at me I tell her that if she loved Luke she wouldn't have done that and that I couldn't keep that from her parents as I do not agree with lying esspecially given the circumstances. While shes still yelling at me apparently her parents and my fiance are standing outside the door listening. They bust in when they caught on and I ask my fiance if we can leave. I felt betrayed and I know he did. So we leave we get to the car he asks why im so shaken and I tell him the guy that ran out was not only having sex with her but he punched me in the face. As expected he's livid so he goes back in and tells his mother what happened. His sister starts to stand up and act like that didn't happen which she was outside so she didnt know. His mom gets angry and starts screaming at him and coddling her. My fiance yells that i take care of all of her kids and that his sister is constantly skeeming and because of her i got huet. His mom acts like it doesn't matter and tells him to leave. So we do. Hes still angry. He decides to go to her boyfriends work and let him know what happened as she has cheated in the past and lied to him about it. Wr go hes very respectful thanks my fiance and shakes his hand and we leave. Then the calls start flooding in. We hurt his sisters feelings and so now his mother is saying she wont help pay for the wedding and she says she wont be there. His sister sent hatfel threatening messages all night to us and his mother wont speak to us. The problem is yes my wedding but also she has 5 other children. Ranging from 10-20 that all need attention. However she refuses to deliver that because shes so stuck on her one child. Her other children have started to do things that are not okay but she doesnt focis on them. My fiance is 20. He wanted just a tad of his moms support and shes taking that away as well. I dont understand how he works so hard and has his own place is getting married and his other siblings are going off the rails and she can't take care of anyone except her.