Ok... so if I witnessed someone littering a public park... I shouldn't be saying anything?
Littering is a crime because it damages public and private property and creates work that costs someone else money to correct.
Being fat does not.
or if I witnessed a girl making herself ill after eating (to bring it back to the health thing)... cant say anything?
Nope. None of your business. Maybe she ate bad fish or has a stomach bug. Not up to you to nanny people who aren't asking for your assistance or concern.
Clearly, I can't go around telling anyone they're too fat if I don't know them, but think about it.... I believe this is a genuine issue and I feel awkward for partially being responsible for prolonging it.
What on earth makes you believe you have any responsibility for what these people eat? Are you selling some dietetic product under the false claim it has zero calories when it actually is loaded with them? Because if you aren't, then it isn't your business. Free yourself and realize that other people are responsible for their choices in life.
Further, why are you judging these people on their weight? Do you live in California? Fat people aren't any less intelligent or sensitive or deserving of mutual respect than anyone else so why label them as less worthy of serving. Christ, the last thing you do is deprive a dieter of food as that sends the body into starvation mode, slowing the metabolism to make losing weight even more difficult. Even if they're not dieting, it's still none of your business to tell them what to do or eat and it's not your fault either.
I'm not trying to be cruel here, but it's like asking a waitress to vet the skin color of people back in the days of Jim Crow (which they did!). "Too dark, send 'em to the back room."
I love how I'm now being accused of being "co-dependent."
If you're taking responsibility for people over whom you have no right to do so, then yeah, you're being co-dependent.