Concerns on Homeschooling Highschool

My girlfriend and I are having some issue with an unexpected houseguest. I’m 32 and my girlfriend is 30. A friend of my girlfriend (who just turned 18) got thrown out of the house by her dad so my girlfriend told her she could stay with us, sleeping on a cot in our rec room. Her original plan was that she would finish her homeschooling, get a job and start paying us a small amount for rent. Once two of her friends were out of highschool in June the three of them were getting an apartment together. I work 9-5 in an office and my girlfriend is on disability.

I began to get annoyed after the first few weeks for several reasons. Firstly, she is loud. Her indoor voice is the equivalent of someone who is hyped up on caffeine and trying to have a conversation with someone across the room at Chucky Cheese and she swears like a trucker. Secondly, she and my girlfriend spend essentially every minute of the day sitting on the computer and the house turns into a pigsty fairly quickly. Third, she has no propriety when it comes to her sex toys. If you are staying with someone, can you at least have to good graces to not leave your vibrator sitting on your cot in the room where my child plays and where I paint’ And fourth, she said her mother would be giving her money for food. We offered her dinner a couple times, and now she feels that it is a given that we will be feeding her every night. Her mother hasn’t really given her much money for food but the food she has she doesn’t share, but she has no qualms with raiding our fridge & cupboards when she’s hungry.

We are now almost two months into her stay and my girlfriend is pissed with her. Firstly, this friend has still not even looked for a job nor done any work on her homeschooling. Second, my girlfriend is on disability for a pain disorder and requires help with the housecleaning on occasion and this friend wont get off her ass to assist unless my girlfriend makes a fuss. Third, our dog had a litter of puppies and this friend wanted one but didn’t have the money so my girlfriend agreed that the one she wanted could stay with us until she got a job and could afford to make payments as long as she took responsibility for the puppy’s training and socialization. This hasn’t happened as the only time she pays attention to it is when it jumps on her in the morning, when my girlfriend tells her the dogs need to be fed or my girlfriend tells her its time to walk the dogs. Oh, and she also asked to borrow money to buy two gerbils as she “loves” gerbils. They get no attention even though she claims she handles them every day (she has yet to notice that we moved them to a different cage 3 days ago).

Essentially, all she does is sit on the couch, talk and swear loudly, and text her new boyfriend (who is a social worker 14 years older than her who lives an hour away, go figure). She hasn’t looked for a job, she hasn’t done any schooling, she doesn’t leave the house, she barely cleans up after herself, and we are both nearing our limit! She hasn’t done anything to better her situation, yet seems to expect us to feel sympathy for her because she left home. Oh, and the two friends she was supposed to move out with in June’ She isn’t on speaking terms with them now.

Problem is, we’d feel guilty telling her to leave because she literally has no place to go and is only 18. She can’t go back to her dad’s, she can’t go to her mom’s and she doesn’t have any friends in town (that we can tell) nor does she have any money. Can anyone offer any advice’
My girlfriend has given her the groundrules several times. If something needs to be done and we mention it her response is “I was just thinking that” or “I was just about to do that” (no you weren’t you’re almost asleep and your face is buried in your ipod under a blanket).

We feel a bit uncomfortable enforcing the rules as we aren’t her parents aren’t trying to be but perhaps we need to change that.
My girlfriend is going the additional step of actively looking for another home for the puppy (the friend hasn’t paid anything or signed any contract), and putting the gerbils on craigslist (as she’s threatened numerous times)