hi TS, this is an interesting thread and i'm learning quite a lot from the various opinions here as well
thankfully i'm not in your situation because i am a student and simply cannot afford the money for a FF! but i'm a fellow D7k user as well, and my D7K is fast reaching 3/4 years of usage
i haven't grown sick of it at all, in fact it's my pride and joy and i affectionately call it nikky.
i think there's a question that's begging to be asked and that's "what do you normally shoot" and whether that would justify a FF camera. since you're using a tokina 11-16, most of us would assume that you shoot a fair bit of landscape and thus the reasonable desire to switch over to a FF
but if that's the case, then why a d800 (or 5dmkIII) and not a d700 (or 5dmkII) instead? i think you have already answered that: because it's a want
but the thing is you're kind of "attaining" 2 "levels" of desire here: from a camera that would suit landscape (assuming you do such stuff, sorry i haven't searched your posts to see if you posted any pictures) or low light stuff, to the newest camera that would suit those areas of photography
i think i've been faced with similar situations before: it starts off with a desire but eventually it ends up as an obsession that somehow "needs" to be fulfilled. I think i'll have to painfully learn how to overcome this.
from my humble point of view, i'd suggest you hold on to the D7K (because personal experience tells me that it's a really great camera! NSC fixed my oil splatter problem for free too!)
if not, then i'd advice against jumping ship to Canon (i jumped over from Canon and it was really a hassle to get new lenses)
but really, as a prudent measure, i think all of us should try to save for a rainy day. if anything, you could donate some money to charity
it'd go a really long way! you might even want to spend some money to go for a holiday to Cambodia or some less privileged country and maybe help out at an orphanage there or something. i'm quite certain that would help. i realise i might be sidetracking, but i did the same thing myself and it was one of the best experiences in my life!