However, as a further suggestion, I would advice not advertising how much you loathe her, since fans of characters don't tend to like when something they like is called 'Disgusting', 'Hentai Waifu', 'Stain on the Mario series', or anything like that and will react to it justifiably negatively.
Its always best to just live and let live.
Its always best to just live and let live.
Why not just ignore Rosalina as a character, any merchandise of her, and any comments towards you about Rosalina?
Its similar to what I do with Bowser Jr, since I loathe him as a character in general.