1. Regarding health -- skinny people can be (or get) sick too. Heart attacks, strokes, diabetes, cancer...they're not "fat people only" illnesses. Yes, obesity is a contributing factor to these illnesses, and an obese person is at greater risk, but there's no saying (unless you know he is already ill) that he is sicker than your average guy. If you don't want to date someone because they might get seriously ill someday, that's a big chance you take with *anyone* whether you realize it or not. He's actively taking action to reduce his risk by undergoing a serious surgery to lose weight. Kudos to him for that.
2. Regarding other people judging you for being with him -- there very well might be some people that ask themselves how you could be with someone who is overweight. There might be people who would ask themselves how you could be with someone with a big nose, or a different ethnicity, or a less-than-perfect job, or a wheelchair, or children, or bad breath, or...the list goes on. Are you interested in dating someone because you want companionship, or because you don't want people to think you're the chick who can't get a date? I know that sounds harsh, but I really think people are happier when they can decide for themselves what a "desirable" person is to them, rather than allowing other people's opinions to determine whether or not they're even willing to give a guy a chance.
3. If you think he's a nice guy and are just NOT attracted to him, but feel guilty for feeling that way, don't date him out of guilt. It's not fair to you or to him. Really examine your reasons for hesitating, and your reasons for wanting to stay in contact with him. It may be that you are meant to be a friend rather than a love connection. It may be that you two are very compatible and would be great together. Time will tell if his flaws will fade as you get to know him, or if you will need to find someone that you feel more comfortable with on all levels. Good luck.
