I feel your pain. Lost one of my zucchini plants at the end of last week. I scraped out the bad areas and covered it in soil, and surprisingly, it seems to regenerating a new (small) plant, but the orginial one is a goner.

I know it's not popular here, but I have been diligent with Sevin, & have also inspected the plants for eggs; but they still got to one of them.

This is my first time ever growing white pumpkins and yellow crookneck squash. One of my younger pumpkin vines wilted and thanks to this forum and a steak knife I got two small larvae out *shudder* and then buried the vine. My squash plants hadn't been looking too good....they were about girdled and I julienned them up right there in the garden so I could kill all the larvae I could find. Then I put the remains in my compost pile with the also hideous black soldier fly larvae. The battle's on.