I just need to rant about my boyfriend's sister..

So my boyfriend's sister found someone willing to rent to me and him, considering we have 4 dogs, but the only condition was, she live with us.

I was okay with it at first only meeting her a few times, she seemed really cool.

But.....living with her....I can literally not take anymore.

Our rent is 500 a month because we share rent. We paid our rent up to 6 months Jan, 1, we've been living together since Dec. 1.

She has just now paid her December rent, not even in full....she gets an 800 check, but yet...She has to pay for a vehicle that was GIVEN to her, couches that was GIVEN to her...

I have bought groceries every single time and the food she makes literally goes to waste every single time, because no one else eats macaroni and cheese with tuna....wtf...

My snacks get eaten up first, my cereal gets taken, literally taken to her boyfriend's house, just because she likes it too....

I've started hiding all my drinks, all my snacks, and half of the actual groceries I buy.

We're currently out of laundry detergent and she has been saying for the past week she will get some...Still hasn't, I need my blankets and clothes washed. I'm not buying it, because I and my boyfriend are not made of money.

I have a baby literally ready to be pushed out my vag any day now and I'm sick and tired of feeling like I'm the mature one. Oh yeah, she's 23, I'm 19. I don't know where I went wrong but our lease is for a year.....I don't think I can do it until December....sorry I just needed to rant about this somewhere she's not able to see.

I've spoken my mind to her and him about this but still nothing has changed.