I'm just kind of musing here, so this may not be entirely coherent...
My mum has a Christian faith, and said that she found her beliefs "comforting" when my dad died - the thought that he's in a better place, and all that. To me, a non-believer, that's just about the only positive thing a faith can provide that non-faith can't. How can an atheist offer comfort to a bereaved believer? I suppose you could be glad that the departed was now free of pain (if s/he had suffered in dying) but what do you say when it was a sudden death, an accident, a child?