This is my response to a discussion on GCM when someone mentioned that they don't like the word "Soulmate:"
I use the word "Soulmate" for Mango sometimes. More often I call him, "Friend of my Soul" or "Soul Friend." He says the same about me, and he had an oil lamp engraved for me with the words, "Beloved, Friend of my Soul." If you think of soul as the part of a person that is immaterial, their emotions, thoughts, memories, etc, then I think that, really, marriage is all about being the friend, or mate, of someone's soul. You aren't a mate only to their body but also to who they are inside that body - their essence, their person.
I think "Soulmate" in the popular media refers to someone special who is the matching piece/the other half of one's soul. While I don't think anyone's soul is split (barring extreme trauma or mental illness) or that people have incomplete souls by themselves, I *do* think that when we marry we seek someone who complements the immaterial part of us...who, sort of, "matches." We long for deep emotional connection with people because that's the way God created us. It isn't surprising then, that when people find a deep emotional connection, they call that person their Soulmate.
In the popular media this is never tough, and it doesn't involve a lot of personal sacrifice. I think that's maybe where your distaste for the expression "Soulmate" is coming from. It's too cutesy, too perfect, in Hollywood. I actually think it's a whole lot of work to be the Friend of someone's Soul. To love and protect and soothe and sharpen the person inside of one's mate...not just the outer world that everyone sees, but the inside immaterial person. And people are constantly changing. So, the way we fit together like puzzle pieces with someone one day turns into roughing up each other's jagged edges the next. We aren't static. We don't just fit into the puzzle & then never move again.