If you've accepted the risk then you wouldn't be prepared to beat yourself up for making a decision that resulted, completely out of your control, in a less than positive outcome. Accepting the risk means making the best of any result.
I don't think you realize it but you are loaded with conflict, the result of which is you can't win:
"I have been blessed with good health, despite obesity" except: "I want to get healthier, " and "I want to be able to exercise without getting so winded," and " I had to run to catch a plane a few weeks ago and I just couldn't keep up with my family," and " I want to be able to roll over in bed without it causing earthquake motion", and " I would love to get off of my CPAP." Are you "healthy" or not? pick one.
Then there is your selfish desire to "My husband and I go to Disney all the time and I would like to take them [the Grandkids]"
You've talked yourself into a fine no-win scenario: You talk about surgical horror stories you've read that lead to death, stroke, being sick forever. Not unsurprisingly these are also major complications of morbid obesity. You can kick yourself for getting surgery and not getting surgery!
Which path will you regret more? Trying and failing or not trying at all. My philosophy is that the path I choose will work out for the best. It's this philosophy or living in regret.
Good luck,
Tek