Soulmates?
I think they exist. Just not always romantically.. I think there are certain people you'll meet in your life who you just connect with more than anyone else and you just know it isn't a typical thing and you understand each other perfectly..
And this person wont be always your "Significant Other". I mean it could be your friend or sibling or parent or teacher or the person you're dating or whoever, it could be just about anyone you've ever interacted with..