Consider the possibility that you are a sugar/food addict and need to cut out things like sugar, flour, white potatoes, rice, and processed foods. I've been pretty successful at losing (despite frequent stalls) by following this. Due to complications my RNY>RNY revision was not successful so I have no volume restriction. I HAVE to record everything I eat. My clinic wants me to restrict myself to 800 kcal a day, but I struggle with cravings even though my body is getting sufficient sustenance. Cutting out the trigger foods (above), helps with the craving but I'm usually consuming around 1000-1200 kcal a day--and still slowly losing.
Here are some books I recommend.