I read the pdboxer thing above. Talk about fucked up body image. I don't understand gay anorexia. I had a guy the other day: 5'11, 125, telling me his was fat. Obviously, loads of mental illness floating around.
Fatness, alcoholism, being a tobacco user, being a doper, being late all the time, all have do with poor self-discipline. When that discipline fails, it generally means deeper underlying issues are at work.
The is absolutely nothing wrong with setting standards. E.g.: if we are TRULY interested in saving LIVES, we need to outlaw fat kids, and not waste a BILLION dollars a day on "the war on drugs." As a society, we have some fucked up views. Here's another example: if a fat person takes their shirt off, they are just a fat person staying cool, but...if I take my shirt off, well.., that's a whole 'nuther story.
Back to standards. As a society, we are WAY, WAY, WAY, to accepting of bad behavior, incompetence, and a total lack of personal responsiblity. If you don't want a fat boyfriend, or a fat girlfriend, tell them so, and if they don't fix it, move on. You have EVERY RIGHT to set standard for those you chose to work for, call your friends, spend time with, and fuck the brains out of. You do NOT have to be all accepting.
If I have a weak bodypart, I don't coddle it, enabling it to so stay weak, or to get weaker. Instead, I set the standard for that part higher, and I work the shit out of it, until it steps up. You have every right to set high expectations, and when folks fail, you have every right to dump them.