I think that fat-bashing is seen as a cool thing to do, and people are more likely to objectify others that they don't like in a negative way without realizing it. I doubt he holds you to the same "standard," so to speak.
One of my old high school friends recently posted a "fat" photo of a girl that was wearing shorts that were too small, and she laughed at it, typing out "gross!" The "fat" girl in the pic was smaller than my friend (and my friend is smaller than me), so you can imagine the amount of humor I got out of the thing.
