I have no where to go.

So I'm 34 weeks pregnant. I've posted about this before a while back but it was a little different. I'm 21, was living with my boyfriend and splitting rent when I found out I was pregnant even though I was on the depo shot. He left me because he decided he can't be a dad and I lost my job due to conflicting schedule with college. My dad said I could come back home until I was able to get back on my feet after baby was born. After losing my job, no one would hire me as I was already visibly pregnant. They didn't say that's why but I'm sure it is. I had no problem getting jobs before. So I've just been going to school for now. Anyway, I'm completely fine with living with my parents temporarily, I know once Im able to work again I will be fine and so will my son. The only problem is that my abusive addict 27 year old brother lives with my parents. He was doing really well before I moved back in so I wasn't worried but he's gone downhill since. His girlfriend moved in with him. He smokes weed all day along with vaping wherever he pleases. He is an alcoholic and bipolar and gets drunk with his girlfriend almost every night. This results in them arguing anywhere between 1 and 5 am. Slamming doors, screaming, etc. They have a chihuahua as well that barks non stop when they aren't home. So that could be 1 pm or 1 am like last night. He barked for three hours while they were at the bar. I had to put him in the garage. My brother is also severe ADHD and walks around the house whistling and talking as loud as he can while also beating things with his hands. Like making a beat or tune on the wall or door. He's gotten so drunk before that he almost burned down the house because he passed out and left food in the oven. The whole thing caught on fire and it was terrible. We woke up to a house full of smoke at 4 am and my brother on the floor. We live in a very nice neighborhood with lots of kids around and our neighbors won't even talk to us since he moved in because they hear him yelling as much as we do. They have also made comments about smelling weed. Here's the problem: my parents complain about him living here 24/7. They don't want him here but they admitted to me today when I expressed my concerns that they're too afraid to confront him because he will blow up on them. He threatens to kill himself when they make any kind of rules. He completely loses it. They won't involve police because he hates them and will do something stupid. They keep saying they're going to give him 2 weeks to get out and then they don't. He's no doubt going to be here when my baby is born and I am scared. I'm scared of my son being around that. I don't want him around weed or vape. I don't want my brother waking him up every time I just get him to sleep. I don't want to worry about my sons well being around someone's who's been charged with domestic violence twice. But I have no where to go. No family that is able to take me in (My aunt offered I stay there while pregnant but not after baby is here). No friends that have room. I don't have much money saved anymore because I have spent it all on things my son needs. I have enough saved for the first two months before I get a job. I can't get my own place yet. I am so completely lost on what to do or where to go. I'm extremely emotional right now and keep breaking down crying everytime I think about having to live with this person any longer. I get no sleep at night because of them and I know my baby won't either. Someone please give me advice, I don't know what to do. I've been trying for months to get my parents to do something and they won't. They're too weak and afraid of him doing something. Don't tell me adoption because I'm not about to give up my son just because of my brother. I know my situation is temporary but I'm still scared for the at least 6 months that I will be here around him.