First, there are people that have regretted having surgery. Generally they aren't on sites like this.
Second, all those bad things that you've read about in the past are still out there. Put them in perspective right next to all the negative effects of not doing anything. Choose wisely.
Third, saying goodbye to your favorite foods forever largely depends on your surgery type. Even then, none of the foods you mention are goodbye forever foods in reality.
In the last month I've eaten McD's. Red meat is in my normal rotation, you can pry my hamburger out of my greasy, dead hands. I've had Peanut butter cups, though not much and not often as I've had RNY and I dump on sugar. In point of fact there is no food or drink that I cannot eat if I choose. I generally stick to my plan, so the worse the food/drink is health-wise the less often I eat/drink a little of it. All things in moderation, including moderation.
Your Doctors work for you. If your Doc is not doing what you need, then you need a new Doc.
You can succeed at this with the proper mind set. It is a big change for most of us. For the better, generally.
Good luck,
Tek