Here is a quote from a pre-race speech before the Leadville 100. I did not run the race, but this quote very much sums up running an ultra, especially a 100+ miler. I hope it motivates you in whatever race you run in this life.
"When the going gets hard. When the time comes and I promise the time will come. When the legs are dead. When the heads done. When the lungs are burning. One time believe, believe with me and dig deep. Take one more step. Turn that step to two. Soon there's an aid station. Keep digging. Soon there's another. Soon before you know it your at the finish line. Your husbands, your wives will be there crying. Your boyfriends, your girlfriends, they'll be enjoying wishing they were with you. Your children will never see a more proud moment of you........Do this and find out that you are better than you think you are."
Run Like a Horse,