It was originally intended as a children's book, but Michael Rosen's Sad Book is very well-written and has helped lots of adults (and children) to cope with grief. He wrote it while he was struggling with his own loss of his son.A couple of weeks ago a beloved family pet died unexpectedly while we were away on holiday. There's an extra 'oh fuck' to this story though, as it happened exactly, to the very day, 40 years after my father died. I could really do with some help and advice on grief and grieving. Books, CBT exercises to help work it through, whatever. It's thrown me back a long way.
I'd also recommend the Griefcast podcast by Cariad Lloyd. She has a different guest each week and they discuss different aspects of grief. I have related to a lot of the feelings they have talked about; maybe you'll find some use in it, too.