seems like you were participating in the social contract of white lies and he wasn't. i find it hard to believe that you wouldn't change a single thing about the guy, given the power, even if he was great (obviously wasn't, though).
you asked. he answered you honestly. I think the answer hurt your feelings because its something you already feel insecure about and your fears felt validated by his comment.
heres the bottom line: his comment bothered you and you told him so.
kudos for being classy and letting him know how you felt. honest communication can be uncomfortable, and should always be undertaken with tact. it sounds like he didn't put enough effort into that. in the future, it may be easier to not ask questions you don't really want the answer to. ...but i think the information gleaned from the conversation told you something valuable about him.
he has the social grace of a drunken rhino. keep being awesome.


I feel that Ive moved on a lot since I stopped talking to him. He's tried to contact me a few times and said he "forgot" something at my house only to admit that he just wanted an excuse to see me. I just prefer people that are more socially aware and sensitive, so just a big red flag for me that he wasn't a great fit for me personally. Also I really identify with your post about your friend.. sounds a lot like what I enjoy doing! I've traveled around the world and am currently getting a masters degree. Thats the main thing that bothered me (besides his insensitivity) is that he said I was wasting my life. I don't believe that I am at all, I am not just my weight. He answered that what he meant was that "I am wasting my time being overweight because I could have better guys if I was thinner" lol. 
Not sure if he just was saying deprecating things because he felt bad or what. But who cares lol. Moving on! Losing weight seems to be one of the main struggles of my life, and it's not easy... but I'm not going to let anyone make me feel less than for being overweight. It is only one part of who I am.