Whenever I feel emotionally overwhelmed, for whatever reason, I find that it helps to read old favourites (whether fanfic or books) - in the case of books, I tend to go for children's books since I know the story and don't have to worry about anything 'bad' happening, and can immerse myself in them. When my father died (nearly five years ago) I passed that on to my mother, and she borrowed my 'Little House on the Prairie' books for that very reason - she found it helped her to 'switch off' for a while and then she was ready to carry on again.