Need help.

My mate got abused by his dad when he was two. He’s 17 now and lives with his mum.

Him and I talk everyday. The other day he was being really distant but he was active on Facebook but wasn’t reading my messages I was confused. So I messaged him I will always support you. But he was active but still didn’t see my message.an hour passed and he was active on and off and still didn’t see my message so I decided to message him I told him I’m just gonna go and he messaged me saying sorry but I kinda want to be alone atm because he finally let his emotions out last night to his mum and told her about the abuse. I understood and said I’ll go but I want you to know you can always talk to me. He said. Yeh Ik and thank u. I replied with anytime okay I’ll go but message if u need and he left me on seen. A few days pass and I still haven’t heard from him. I was getting worried like I did something wrong or something because I don’t understand how he is feeling because he told his mum about the abuse from his dad and his emotions I haven’t been through that so I don’t really understand how he’s feeling but he was active a lot today so I decided message him to see how long he wants space for. He didnt read my message but he was still active so I sent him a message saying please talk to me but he’s not active now. Can someone please help me understand what he’s feeling and what I should do.