My friends stopped talking about my person who died

It's been eight months and I think my friends have moved on from mentioning my brother. They don't ask how I'm doing with it anymore. They change the subject when I bring him up. I know they're not being cruel — grief makes people uncomfortable. But it feels like he's disappearing twice: once when he died, and again when everyone stops saying his name. I still need to talk about him. How do you keep someone's memory alive when others have moved on?