I'm so sorry you're in pain. I have no words that will relieve it.
Everyday sucks when our loved ones are no longer with us, but anniversaries rip the wound right open. I thinks it's only natural for you to be grieving this hard.
As far as your father is concerned, does he have any brothers or sisters you could call and talk to about him? Or a friend of his? You need to let someone know. It sounds like he is immersed in grief and needs help.
Is there someone at school you could talk to?
Hang in there. Maybe someone else will come along and offer some ideas on how to help.