Fasts are sometimes done short-term for cleansing, but I don't think anyone recommends fasting for weight loss purposes.
It's hard to keep going on any program for more than six months--people don't understand just what a challenge that is! But, many people here on 3FC have stayed on their plan for longer than that--some for much longer. So, what you need to do is find a way of eating that you can sustain in the long run. It has to
(1) Fit with how your household is eating,
(2) Fit with your own style--e.g., if you don't like cooking, then a program where you have to cook special foods all the time may not be right for you. And vice versa.
(3) Go with your life. Do you have a job outside the home? Can you take a lunch to work? Do you travel for work a lot? If you are someone who stays home, then sometimes it's easier to get things under control.
(4) Be something that's flexible enough that you can work around daily challenges and have some variety, but still restrictive enough that you can keep losing. Lots of members like calorie counting for that reason.
So, keep trying! If you want to do a raw foods day, that's fine--but try to keep it in the context of a bigger picture.
Be sure that your plan contains strategies for when you've reached your ideal weight and you want to mantain. That's the hard part. That's why "diets" don't work--people stop "dieting" and go back to old habits...
Good luck! Keep on!
Jay