What you gotta do is lift his spirits up. Start encouraging him to do mundane things he likes with you. Depression is what he’s going through. No one wants to admit it but he probably feels ashamed of himself. I saved my brother from suicide and took his journal and realized wee are all in this together. I felt the same way he was feeling. We lost our dad to stage 4 cancer and just got stuck in a depression cycle. It’s hard to explain it but even if y’all haven’t lost anyone he could just be depressed with his situation. You can try to get a job or start job hunting and encourage him to get a job with you. Mention car pooling and being able to have thesame schedule hopefully so if you guys ever needed a ride or something you guys would be able to get each others backs. Idk but hopefully it helps. I love working with my brother