[VLM]

"That doesn't explain how someone can just let it happen to the point of suffering of it every day"

Abstract out the obesity, and you've described every chronic health condition, ever. A huge number of emergency room admissions read something like: I thought it was normal that road signs were getting a little blurry after 40. Sure my heart screams in agony when I climb stairs, but who's doesn't? My knees are in crippling pain for days if I hike more than two miles. Every time I drink, I drink till I pass out or are arrested, but doesn't everyone? After I eat sugary food (aka modern american diet) I feel faint and fuzzy, that's normal, right? I hear voices in my head more often as time goes on. Why how odd that pain pill has smoothly and gradually gone from something to make life bearable after surgery, to life is unbearable without it, to life is unbearable even with it.

People tend to be pretty good at getting medical care for acute things like bleeding out more than a quart or so, or broken bones, but not so good at getting help for chronic things. Gettin fat is obviously not an acute problem.