I’ve pondered this a bit but certainly not to your degree. You’ve certainly raised a lot of interesting questions. I’ve never fallen in love with someone before (atleast to how it’s been described to me) but the idea of having a best friend to cuddle with is what an ideal relationship for me stands to be.
But I’m autistic so maybe I don’t experience these feelings the same way? It’s as you say, romance cannot be measured nor tracked. I can only guess if I’ve ever felt the feeling.