So sorry to hear about your Gran. The same thing happened to me when I'd been here 6 months, then a double whammy as my other Gran died a few months later.
Its tough hun but just remember all the good times you had together because they will be in her thoughts too.
I know its hard being so far away but why don't you do something special this end to mark it, it might help with your closure. I'll leave that for you to decide.