Maybe you should talk to a councillor, <3AmyMathews. It could really halp to get all those emotions out, and make you feel better.
And if your mates do that, then they aren't true mates at all, and you'd be better off without them if they treat your feelings like that. And with the bullying, have you talked to a teacher? I know how it sounds, but it helps, as they can put a stop to it. They are only picking on you becasue they don't like themselves, and need something to distract them, so after you tell a teacher, ignore them, and they will get bored. And with your family, maybe it would be a good idea to get everyone together, and remember him happily, and all your happy memories. I know that helps me to do that when I think about my grandfather. Or you just need to let grief run it's course. Soon you will run out of tears and sadness, and you can remember him without crying. Trust me, I know.
okay, PM me if theres anything that you want to talk about, anything at all. I'm here if you need me.