Mercedes Lackey, in her novel "Jinx High" has a character that is an author, or romance serials ( like Harlequin). she had the character state: there is no such thing as writers block, I can't afford to have it. I put 8 hours a day into work, no matter what is happening in the story. if I am stumped, I plot out other stories until I get a spark to finish the one working on. but I work 8 hours a day, every day. this seems to me to be the best way to break writers block myself, continue writing, but on a different story, sooner or later the inspiration to get the other story will come to you.