The problem with taking a day or two off from writing, sick or headaches aside, is that it's so hard to get back into the discipline once it's been broken...
Poetry is not a turning loose of emotion, but an escape from emotion; it is not the expression of personality but an escape from personality. But, of course, only those who have personality and emotion know what it means to want to escape from these.
I found that quote while searching for Dickinson articles and coming across a page of quotations. I wish I knew the source, but more than that-- I wish I could get more of a context for this quote or, better yet, an explanation of it from Dickinson herself.
It reminds me of what Madeleine L'Engle wrote in her book Walking on Water: Reflections on Faith and Art. In one oarticular chapter, L'Engle writes about the discipline of writing and how one can reach the point where he or she moves beyond the acts of writing and the words and steps aside, letting the writing take over and become more than the writer could have ever meant for it to be. Instead of bringing the words to the page, the writer enters into the words as they develop and falls sort of "through the looking glass" into whatever else could be-- things that could not be plotted or planned or contrived.
I believe that there are moments in writing where, as a writer, it is possible to move beyond the here and now, beyond emotions and personality. Yes, some of the writer's personality is inherent and will possibly always be found in traces in the work. But the conscious and deliberate aspects of writing fall away in these moments, and the inner truths and beauty of the writing come out and develop whole new lives of their own.