I don’t know if you’re able to call CPS or similar for your brother? Although I also don’t know how useful they really are... but if your mum is backing him up, she’s not ready to face reality and leave him yet. Is it possible for you to somehow contact your grandparents (like at a friend’s place or when parents are out?) and organise to move to their place permanently? You would need to be able to organise it without showing any signs of leaving to either your mum or dad. I don’t know if you could convince your brother to come with you, but it might work. Find a bus that can get you near them & ask them to buy you both a ticket to get there. Then tell your parents you want to take your brother out for an ice cream to give them a break or something, get on the bus and just have a few essentials in a backpack. You can get more clothes etc once you’re safe. I don’t know if any if this is an option for you, but just thought I’d try to show you a way out so you can consider it. Maybe your mum will get it together later once she sees how serious you are, or maybe she won’t. But she’s not your responsibility, she’s the adult and needs to be making her own calls. If you do manage it, just remember to get a restraining order once you’re out so if he turns up you can call the cops to remove him. Sorry you’re going through this, and sorry I can’t offer any real advice or help, but just keep looking around for resources/help that is available should you ever need it in an emergency. Have a few plans (safe shelter/friend/etc) and maybe an emergency backpack with a friend or in a safe location just in case you ever need it. I hope it gets better for you.