All good advice, and I follow much of it. I should note that due to addiction issues in my family, I tend not to be an absolutist about these things, nor to stigmatize things (I don't have a 'cheat day' or 'sneak' a treat, for example; sometimes I just want a snack, and that's ok). But there's actually an interesting challenge I've dealt with at points in my career: you say _only_ eating 3 meals per day, but I have seen people struggle mightily with obesity because they were only eating 2 or 1 meal per day regularly, which threw their entire metabolism out of whack. "Don't do that" was simply not a viable response for them because at times they simply couldn't afford more food. (To be clear, that's not my experience, so I can't speak to it directly, but it's an interesting challenge to "eat 3 square and you'll be good".)
Coming from a family of alcoholics, I'm also very familiar with the moral judgment issue with addiction. It _must_ be a lack of control that makes that man drink, etc. There's been quite a lot of success destigmatizing alcohol addiction in the last half century, so it's even more stark to see exactly the same thing play out with so many conversations about food and weight. It _must_ be that fat man's lack of control that makes him fat. Often it is. But there are so, so many other factors. I actually think that's part of OP's larger point.
I also come from a family with substance issues, alcohol et. al. You can use your imagination.
I focused on the water thing because it is so, so easy to smash a 20oz coke without thinking about it, twice a day even. I’m sure I don’t need to inform you about the nutritional information of coke, but 40oz a day negates any kind of diet or exercise two-fold.
I also made the point about 3 meals completely because of metabolism and the bad effects of eating only once a day. There is however value in skipping breakfast and only eating lunch and dinner, but not if you just make up for breakfast with the other two meals.
The world isn’t black and white, absolutism is never a good thing unless you’re designing digital circuits or some other “there is no other choice but binary” but there already is an exception to your rule.
Keep an open mind. You sound like you’ve talked yourself out of lots of things and seem to have accepted defeat and blamed your circumstances. Coming from the same background as you I would encourage you to at least admit to yourself the things you already know and excuse away. When I finally had that moment it was a game changer.
Coming from a family of alcoholics, I'm also very familiar with the moral judgment issue with addiction. It _must_ be a lack of control that makes that man drink, etc. There's been quite a lot of success destigmatizing alcohol addiction in the last half century, so it's even more stark to see exactly the same thing play out with so many conversations about food and weight. It _must_ be that fat man's lack of control that makes him fat. Often it is. But there are so, so many other factors. I actually think that's part of OP's larger point.