I know that you may feel disappointed and feel like you have failed. But you haven't. Unfortunately, we don't get diabetes because we are overweight, we are just unlucky. And you shouldn't think you have failed, instead you should beam with pride. You lost 100 lbs and you were able to go off insulin for years. You should be proud. Insulin doesn't have to mean weight gain. I started a little over 2 years ago. I'm now on Levemir and Humalog. I am within 5 lbs of the weight when I started. If you still eat properly, exercise and keep your blood sugar controlled, there is no reason to think insulin causes undue weight gain.