I think people don't know what to say. And they are sorry you're hurting. Seeing others hurting makes us uncomfortable and wanting to rush in and help.
But the truth is that sometimes you just have to feel the hurt. It's there now, in the moment. It hurts. It will get better but right now it hurts. I think it gets better when it's allowed to be instead of being denied or covered up with pretending it isn't there or that it isn't what it is.
I'm sorry you're hurting from the loss of something very important, the feeling of being in a caring friendship.