ammonia 0-.25, 0 nitrites & salinity @ 1.025The "corkscrew" arm tips are almost always a sign of impending death either from senescence (which correlates with the behavior change), foul water or stress. She may well have already laid eggs and was captured in her end days (often the coloration will be a whitish grey and the mantle will be quite floppy and difficult to control). I suspect this is the case but immediately check your water for ANY ammonia or nitrites to be sure the problem is not that you need more bacteria. Also check the salinity.
Not all animals lose their ability to color in senescence (at one time @Neogonodactylus dobuted that this is a senescent sign - I think now he agrees it is common but may not have been with the species he most often works with in the lab). IMO, the cork screw arms are always a sign of severe stress but senescence is one of the factors that could cause it.I'm sorry for your loss. Thanks for documenting all of that. D, point taken / agreed on the corkscrew arms being problematic, but is senescence seen without the octopus also turning white?