No, she’s not. She may be well aware, objectively, that her friend is more conventionally attractive than she is, but a total stranger in the process of providing a service to the OP is being rude and officious in telling her she’s ‘brave’ to have her friend as MOH.
OP, bear in mind that people’s opinion of other people’s looks and their estimations of their own are often highly subjective. I regularly hear women admiring the looks of people who are nowhere near as good-looking as them, or wrecking their own existing good looks in favour of some plastic ideal.
One of my undergraduates, whom I last taught in December, came to see me yesterday, and was barely recognisable. In December, she was a pretty, fair-skinned, fair-haired girl, very delicate and natural-looking (slightly Baby Spice vibe, but not brash?). Yesterday she was wearing a dark fake tan, had had something done to her face (surely not Botox at 20, but something?), had gone bleached, and had giant lip-fillers. She said ( a propos of applying for something) that she ‘was proud of having done a lot of work on myself’, and I think she genuinely believed she’d ‘improved’ her looks, but objectively, she now looks like Janice from the Muppets.
My point being that some people can’t see either their own beauty, or other people’s, and some just have terrible taste.