Hi, I quit the first time I tried the Master-Cleanse after a day and a half. The hunger took over. I'm now on day 8 (and can't believe it). It's been tough for me though. I've considered quiting a couple of times, but what held me in is knowing that I'm doing this for the right reasons and I DESERVE the rewards. You'll never make it through unless you truly believe that you're worth it. And you are! For your kids sake at the very least.
I also found that telling everyone I possibly could helps keep you accountable and affirm that you're commited. They always ask how it's going and nobody wants to confess that they couldn't cut it.
Hope this helps! Another thing: when I'm feeling lousy, I try to do something nice for myself like take a hot bath or shower with lots of yummy soaps.
good luck to you! remember that everyone is here to support you.