That must have been really awful.
It has probably happened to others out there: I've heard accounts of turtles eating eggs, too.
I haven't had that happen, and in fact, that is one of several reasons why I try to keep an eye on the girls this time of year. I try to get a good look at where they're digging, and then go in the next morning to carefully uncover the nest & remove the eggs for incubation inside.
Another reason is that, in a confined space, another female may accidentally uncover a nest while digging her own: last year we had a close call, when a nest was dug right next to where one had been dug a day or two befor. Luckily I had already removed the eggs from the first nest, though.
Stephanie