Why do people stop carrying about your loved one being gone.

Two days ago was a month ago today that my grandfather passed. It’s like after his memorial, even suddenly stopped caring and now everything is moving on with our lives. I feel like I’m the only one that hasn’t moved on. My grandma is okay and she still heartbroken of her husband of 60 something years is gone. Nobody from the family once called to check up on me accept my aunt, uncle and my half siblings.
I lost another friend because she said my attitude is ugly and my grief no excuse to be rude.
Everyone stopped asking how I am and act like it never happened.