Tsh at The Art of Simple blog wrote THIS great post on "How to Say Goodbye".
The point that stood out for me is to give yourself permission to be sad, then give yourself permission to NOT be sad.
My 8 yo suffered the heart-aching loss of her best friend moving away this summer. It's been three months, and she's done a whole lot of grieving about the unfairness of life (and adults who get to make moving decisions for their kids!)
I've done my best to really hear her feelings on this, but I think she also needs to hear that not being sad every moment doesn't mean you don't care anymore, or that you love your friend any less. Hmmm.