It realises the self-imposed facade of body positivity it's indoctrinated itself with is not susceptible to the rigours of real life and normal people's attitudes. It understands that as soon as she's confronted with anyone who hasn't bought into the same delusional ideas she's force fed herself, her self worth, which is actually hanging by a thread, will instantly be destroyed  In other words, on some level, they clearly know they're lying to themselves.  Advice? Eat less, move more.  I'd also recommend eating high-protein stuff that makes you feel full so you stay within calorie limits, but fats also eat when they aren't hungry.  A particularly poignant example was when Amberlynn Reid was on diet pills, wasn't hungry at all, and still insisted on filming a "mukbang" where she forced herself to eat lots of crappy pizza.  Why the fuck are you taking appetite-suppressants, then.