I'm obese. Would like to hear from people who have tried Gastric Byp.?

Please only serious people. I am 26, I am 5'6" and I weigh 254lbs. I prepare every meal with the best of intentions. Low sodium, low fat. I quit drinking soda 3 months ago, and not even one pound has disappeared. I have a two year old daughter, so of course I'm active. I also walk two miles at least twice a week. I just can't seem to get anywhere.