Good job sticking with it!
I did the Fazio Farms race today in Portland and there were a lot of people getting flats. They were offering some kind of prize for DFL, so a few people ran it out, but more just called it a day. I didn't think much about that until I saw the guy who ended up winning the A race running his bike to the pits. To be fair, he flatted in a fairly convenient place -- he had maybe a quarter lap to run, but most of it was chicanes through loose dirt that I was starting to think would have been faster to run anyway. To his credit, though, he was in second place when he got the flat and made a really impressive comeback to catch the guy ahead of him (two or three laps later).
Personally, I had my hopes finally winning something at a cross race foiled by a guy with the kind of determination you're talking about. I got off to a terrible start and am pretty slow to begin with, so I thought I had DFL in the bag, but then some guy flatted on the second lap and ran his bike for a lap and a half to finish a full lap behind me.