@bogglesauce you can do anything that you put your mind to. What others achieve has nothing to do with what you can do.
Surgery is a tool only, how you use it is up to you.
Little by little you will need to change your relationship with food. Eat to live not live to eat.
Follow the program, exercise, no flour, sugar, bread, pasta, rice or potatoes. Protein 1st, non-starchy veggies second. Non calorie liquids only, stopping 1/2 hr before & after meals. Eat when truly hungry, stop at 1st sign of full. While I treat myself occasionally, this is now my life and I never feel deprived of anything.
A helpful mindset that I heard is to tell yourself/others, "I don't eat that" rather than "I can't eat that" A simple thing, but very empowering.
Pre-surgery, I didn't weigh much less than you. Was 275 the last time I weighed myself, so was probably closer to 300. Got to 115, been maintaining 122 for almost 4 years.