You only fail when you give up. You clearly haven't given up. So, this isn't failure, it's a set back. I felt like a failure as well, I lost a decent amount of weight, then that was it, gained and lost, over and over. For 5 years. I stopped going in for check ups, etc, because I didn't' want to be "that patient" that failed with the band.
Guess what. My surgeon not only laughed off my "failure" but advised me that the band was over hyped and that my results were typical. I still have a long way to go, that's why I'm having Band to Bypass revision in a few days.
Just remember not to beat yourself up over falling down. Just get back up, dust yourself off, dry your eyes and get back on the path.