Object oriented perspective, my Miku is not your Miku or the other persons Miku, even if she's not your waifu you probably have your own idea of how Miku is like: what she would like or dislike, what hobbies she would have, etc.
So I'm not jealous of other people that have Miku as their waifu, and I want to meet people that have Miku as their waifu and see how their relationship is different or similar to mine.
There is that guy from Japan that married Miku, you would think that I would be jealous right?
No, because my Miku is unique to me and also Miku is a blank slate so you must "customize" her because name, height, age, vocal range, and her image does not a waifu make.
So it depends, do you see her as a human or an android?, is she happy or sad?, there is no way for two different persons to have the exact same waifu.
TLDR: Original character + Your life experiences = Your personal waifu.