I am an English major and just completed my Masters in Education. There were times when my depression did get the best of me when it came time to focus on my writing. But I was able to find ways to help keep me focused. It may sound counterintuitive, but placing small tokens of life events--momentos arranged in vignettes--around my desk helped me to rest my eyes on familiar objects so that when I drifted, my eyes at least fell on familiar, peaceful objects. Sometimes all it took was zoning out on those familiar objects to provide the inspiration I needed to build my essays on.

Have you ever seen the show Criminal Minds? The character Penelope Garcia places bright, cheerful tchotchkes to distract her from the ugliness she has to see on the screen--not that we are looking at macabre pictures (lol--even though a blank screen can be kind of horrifying to a writer).

Hope this tip helps.