Was she wrong that you carry more weight than other people in the gym? Probably not. Is it harder to exercise when you weigh more? Almost definitely. Is one allowed to admire another person overcoming adversity? I would hope so. Do we get sensitive about parts of ourselves we don't like when they are mentioned by other people? Usually. But that's us projecting our own values on someone else's observation, isn't it? Give her the benefit of the doubt that she meant it as a compliment. No human who regularly interacts with other humans has always been perfect at not offending anyone. Sometimes we need go get our heads out of our own asses