Why isn’t my brother communicating with us?

My 21-year-old brother took his life in November. We loved him unconditionally; he loved us even more. That’s why I find it so surprising that he hasn’t tried communicating with us in any way. Especially with my mom, who I know talks to him every single day. She is suffering even more than I am. It makes me think that either he wants nothing to do with us, or he just simply doesn’t exist anymore. I’ve heard so many people talk about all the signs their dead loved ones will give them; if we have souls that remain after physical death, I am shocked that my brother - one of the most caring people I have ever known - wouldn’t bother to tell his family he’s okay. I’m losing what little faith I have.

Edit; thank you everyone for all your messages and condolences - everything makes a lot more sense now.