I've been thinking a lot about that lately too. So far, my husband kids and parents know. I've been approved, but my first appointment isn't until October, so I haven't told many others. My current thought is that if it was a heart bypass instead of a gastric bypass, there'd be no question. It's a surgery that my doctor recommended for my health, more than anything, weight loss is a welcome side effect.
There's always going to be judgmental people. When my son was diagnosed with type 1 diabetes at 14, so many people told me "it must've been the sugar." No...he was 100 lbs and his pancreas quit making insulin. He's 21 and I still have to educate people that think he should have grown out of his juvenile diabetes.
So, if people ask, I will tell them, heck, I may even tell them if they don't ask. If anyone actually has the nerve to tell me I took the easy way out, I will come up with some great comeback lines (I have time to collect them )