I’m hesitant to call it a myth because there are people out there who believe in this concept of finding “the One”. We wouldn’t have come up with another name, soulmates, for it if some people out there didn’t believe it was fully true or true to a degree.
Love is too abstract of a concept to fully change it, we can evolve it certainly. I know these don’t really compare in a way, but love isn’t like global warming in which we can actually take steps to stop destroying the atmosphere as we are, love is an intangible concept that isn’t as malleable. The definition of it depends on the person, it depends on the time period, and depends on the culture. To say that it’s a myth is, of course, your personal opinion, which I fully respect, I just don’t want to bash it too much in case there are others reading who do believe in the journey to find “the One”. Yes, we can’t back it up with theories or statistics or implement the scientific method to find out if “the One” really does exist for people, but that’s okay because not everything can be explained, or needs to be explained, by science.