Ah, yes, this reminds me of my mother’s favorite sayings,”if not now, when?” and when pressed, later followed by, “tomorrow.” This means never. I’ve done your suggested exercise of writing about why I sometimes can’t write, a stream of consciousness, if you will, and it releases the angst of facing a blank page. I also remind myself that I will probably delete a good portion of the beginning because, as I write, the real beginning will reveal itself way down the page (or two). This also helps relieve the stalemate of staring at a blank page. Another way to start is to write in pieces, then later assemble the pieces together into a whole story. If I discovered a well documented event in an ancestors life, I would write about that event, then save it for the larger story. (I once heard a famous author of fictional works describe this technique; he wrote scenes on seperate pages, taped them across the wall, moved the pieces around until he liked the story order, then wrote the transition scenes to tie them together). Of course we write history, not fiction, but we can fill the inbetween genealogical scenes with historical facts that influenced our ancestors lives and decision making. I once wondered why several related families who lived and farmed near each other all moved away after a short time. Then I discovered the summer they moved away experienced a devestating drought and massive grasshopper invasion forcing everyone to abandon the area. However it works for you, just start! There’s no time better than today.