Going Crazy

Ok so I am a 24 year old mother of two. Right now me, the kids, and my boyfriend are living with my parents. We needed a change of environment and decided to move with them when they moved to North Carolina. We were only supposed to live with them for a couple months, but with everything we had going on, it wasn't possible. We are finally caught up on everything, have the money the move out, and are just waiting to hear back from this one house.
Now, the reason I am going crazy is because of my mother. She has not been working the entire 7 1/2 months we've been down here. I haven't been working since Christmas Eve. Ao we have basically been together every day for 2 entire months and its killing me. Emotionally killing me that is. She has an attitude about EVERYTHING these days and her attitude is affecting mine. I get annoyed with things I normally wouldn't get annoyed with and I end up taking it out on the people who don't deserve it. (Luckily my boyfriend is understanding in this department because he can see it happening.) But lately she keeps making these comments that just irritate the shit out of me. Like tonight, she says "it really irritates me that your childrens shoes are everywhere and they're not together." Does it really matter? They're not her kids, and yes I understand I live under her roof BUT she's not the one who has to find matching shoes, I am. If I don't care, why does she?
Now last night she pissed me off and I went to bed pissed, and thus woke up pissed. Now to understand why I was pissed I must tell you that she is a HEAVY pot smoker. She normally becomes more of a bitch when she doesn't have it in her system. But, she had a job interview yesterday and got the job (YAY FINALLY) and she had to go for a drug screening today. Well last night I asked her how she was going to pass the drug test and she said "I still have my synthetic urine remember?" (Now just so you understand me: I don't care if people smoke weed, I really don't, but I am NOT a believer in using synthetic urine or someone else's urine to pass a drug test. If you know you have a job interview coming up, no matter if you get it or not, stop smoking to get it out of your system.) So I told her that I forgot about it. Then she, jokingly, said, "I could always get you to pee in a cup." To which I replied, "Nah I don't think so." she asked why not and I told her that I don't even like peeing in a cup at the doctors office. She got defensive and started acting like she couldn't believe I wouldn't pee into a cup for her. She then got mad and said, "I was just fucking kidding" with a HUGE attitude. I was playing along with the conversation, but with a hint of seriousness, and she blew it way out of proportion.
I can't wait to get out of her house!