If I were you, I would try EVERYTHING else before considering gastric bypass. Because GB is for life, and if you find you don't like it, you can't easily get it reversed.
I've lost about 30 lb. on low-carb -- the fewer carbs you eat, the less insulin you need. Exercise, and making sure you eat enough protein protect against muscle loss -- what you want to lose is fat, not muscle.
Getting your thyroid regulated, and making sure you are getting the nutrients you need is also important. I was low on vitamin D, and am taking a supplement, and I had a thyroidectomy due to a goiter that was so large it was interfering with swallowing, so I take thyroid pills as well, and I think that has helped.
I DO know people who have had success with gastric bypass, but they were all Type 2's, although one of them was later rediagnosed as a Type 1. So it's not out of the question, but I think it should be a last resort!