consdering revision to bypass but feel guilty about it

Best wishes to you. You are very young and shouldn't feel miserable or a failure because of a procedure that didn't work. Your doctor should have given you better advice. However, I think you should get counseling regarding your relationship with food. It will help you in the future deal with maintaining your loss. Even with RNY revision, calories, sugars/carbs, and quantities have to be accounted for. RNY is not an automatic success. People call it a tool but the real tool is your brain, you have to change the way you relate to food.