I know exactly what you mean unfettered moth. My mind does this to me a lot during fasts and has beaten me more than once making me end it. It goes through a process of trying to convince me it would be a good idea to stop. It rarely is the best idea to stop but sometimes the persuasion is just too overwhelming to resist anyway so I grab hold of any little reason and run with it.
The benefits of staying on the fast are obvious. The detox that is happening now, the fasting crisis, will continue to it's natural end and whatever is causing it will be gone from your system forever. Whereas breaking the fast now will interrupt that process and possibly, or very likely, some of what the body is trying to accomplish now will be stopped and will have to be faced again on another fast. However, sometimes that is unavoidable. The main thing to remember is that if you do break the fast be focussed on breaking it correctly. Then the detox will continue if at a smaller pace and the effect on your body of breaking it prematurely or during a crisis will be minimal. Also and perhaps most imporantly, you will be getting your body and mind used to breaking a long term fast properly and this in turn will prepare both to better face fasts in the future.
Hang on if you can! You are being very strong but however the struggle ends you have had great success already, remember that. :)