From my own personal writing experience and from all the writers I've worked with, I've come to believe that writer's block is more aptly described as a writer who does not know her story well enough.
Rather than succumb to the feeling of blockage and to learn more about your story, writers spend time outlining and/or pre-plotting, tracking scenes and/or creating a plot planner. Often, such strategies help to stimulate ideas and the writing begins flowing again.
Another strategy is research. Whatever time period your novel, memoir, screenplay covers, every writer benefits from researching for just the right details and exploring a broader range of what was happening during that time period historically, politically and with fashion and trends and fads. Often this sort of research stimulates ideas for scenes and the writer finds herself writing again.
Caution for all strategies -- use them until you are inspired to write and then give up the strategy to write. Employ the same strategy again when your energy flags and you feel "blocked." Plotting and tracking and researching are secondary to writing.
Use any of the above strategies or any you have found helpful to roll the boulders out of your way and you'll find yourself achieving your long term goal of finishing your story.
To familiarize yourself with the Universal Story and the basic plot terms in the above blog post:
1) Read The Plot Whisperer: Secrets of Story Structure Any Writer Can Master (Now also as a Kindle edition)
2) Watch the Plot Series: How Do I Plot a Novel, Memoir, Screenplay? on YouTube. A directory of all the steps to the series is to the right of this post. 27-step tutorial on Youtube
3 Watch the Monday Morning Plot Book Group Series on YouTube. A directory the book examples and plot elements discussed is to the left of this post.