I had picked up a new James Lee Burke novel: his highly-rated The Tin Roof Blowdown based in New Orleans after Hurricane Katrina. I turned to the inside back cover to read the blurb:
...his novel The Lost Get-Back Boogie was rejected 111 times by publishers over a nine-year period. When it was eventually published, it was nominated for a Pulitzer Prize!
Print that out and stick it above your type-writer and get back to work.