My boyfriend is home

My boyfriend is home with me and my mom. For those who haven't seen my post, his cousin Abby and Liam molested him by forcing him to give Liam oral and when he told his mom his mom didn't want to report it she took him BACK to his cousins and left him there to work it out. They beat and raped him... He ended up in the hospital and his mom didn't even call because she didn't want to get Abby and Liam in trouble. His grandmother is the one who called 911. My mom has emergency custody of my boyfriend because of his mother's neglect. He seems to be in a lot of pain. I offer to help but it seems to upset him. He will go use the bathroom and I'll hear him groaning in pain just from using the bathroom.. My mom let's us share a bed because I'm on birth control but we definitely wouldn't be having sex rn even if I want on birth control. My mom seems to be able to comfort him better than me since she is also a rape victim. He will sometimes pee in the bed and I'll wake him up and say "Babe you peed yourself again". And he will get angry and scream fuck real loud. It doesn't feel like I'm helping and I'm his girlfriend. Anyone who has helped someone who has been sexually assaulted... How can I help. Or if you have been sexually abused how do you think I should help?