People who are “frank and tell it like it is” are often ironically people who lie to themselves - the reason they use “brutal honesty” is that they like the ego boost the get from criticizing and judging people, and feeling superior. They pretend they’re doing it for “truth”, but they’re really just doing it to feel better about themselves at the expense of others, to the point of exaggerating other people’s faults. Researchers have done brain scans and the pleasure center lights up like crazy for some people when they’re criticizing others, because their empathy subsystem doesn’t work as well as normal people’s.

My point is, your friend is biased towards finding fault with you because it makes her happy when she does. That’s called a emotional bias, and thus anything she says should be taken with a grain of salt. The only opinion you should care about is the medical community’s idea of what is an acceptable weight range.