How do i handle my 17 disrespectful stepdaughter who just came to live with us about 2 years ago.?

2 years ago my husbands daughter came to live with us. this was hard enough as it was having her move in but it was also the first time my husband had seen his daughter in 14 years. she was a troubled child living with mom and stepdad. she thought that coming to live with dad would be all roses. she has no respect at all for my husband and it is worse with me. she has a mouth on her like a truck driver, she lies about anything and everything. she is supposed to be a senior however she still needs 11 more credits which comes out to still another year and a half. she turns 18 in july and quite frankly i want her out. she just shaved off half of her hair and thinks she can go get a job in a local casino as a bus person. i can't see anyone hiring her except a tatoo shop! she and i recently had our worst argument yet. of course it is when my husband is gone. it always is about trivial stuff. for the most part it is her defiance and lack of regard for house rules and chores. when i try to explain that when she does stuff half a--ed it isn't going to fly. rules and chores are expected to be followed and done properly. and trust and believe she doesn't have much to do when it comes to chores. anyway because i had to tell her about finishing the kitchen she of course said she was done and that i am being a ***** and adding more things for her to do. words were exchanged and then she pushed me. she is quite a bit taller than i, and quite frankly i have no doubt in my mind that she could do bodily harm to me. my husband is a good father and trys very hard under the circumstances in which she came to us. he is open with her and she still lies about everything. the way she talks to me and curses at me really makes me feel as though i have lost control in my home. as it is right now, she and i have not spoken i a week. i wrote her a letter after the last argument and basically told her that this was the last time i would be treated like. arguments with her in the past have ended in a bad exchange of words then an hour or two later she acts as though nothing happened. this was the final straw. it is very tense around here and i don't like to be in the house alone with her. what kind of way is that to live? am i wrong for wanting to kick her out when she turns 18? she told my husband that she plans to leave on her birthday. so he then said well thats okay cause your out of here anyway. better make arrangements. honestly i am so scared that we are going to be stuck with her forever!!! she has no clue as to where or what she wants in life. college is out of the question since she can barely handle high school. we were thinking on the military. please advise......i could use any and all advice