lol@alphacat, vet asked if she was a houdini and upon confirmation issued a 'softy collar' that can be tied as tight as needed. they had it on her twice, and a third time from me. shelved. and luckily hasn't messed with it with some coaching. thanks!
Aw glad you got to the bottom of it. Sometimes revolution doesn't always eliminate the worms but it is great for prevention. you may want to ask your vet about Pyrantel (it's very inexpensive) to get rid of the worms, then keep her on the revolution as a prevention.
cprcheetah, thank you for the thoughts. day 3 into treatment and found this. thought she ate a rubberband until rinsing it after removing it from her litterbox: