Haha....I love topics that hit home.
I'm going to put another spin on the question, and I don't want people to feel bad after reading this.
I still believe in soul mates. My husband and I fit like a glove. What one partner can't do, the other partner can do. In a way, we're total opposites, but in a good way. Everything we enjoyed, we did together. Even other people commented on our combatibility, and love for each other.
Then, one day, he tried to take something away from me that was my very essence of living. He almost destroyed me. It was so bad, I insisted that he start seeing a professional to figure out why he did what he did.
Now to my spin. Is it possible that even though you are soul mates, if one partner doesn't know his inner self, and grew up suppressing any spiritual knowledge, then he throws away the opportunity of having a soul mate. The masculine reference was no accident, haha.
For example, King Henry viii, his true love was Anne Boleyn, though some argue it was Jane Seymour. Isn't there rumor that Donald Trump's true love is Ivana. My father never stopped loving my mother, even though he remarried. My father inlaw never stopped loving his deceased wife, even though he has a girlfriend. And if I chose to follow my human nature, I know that neither my husband, nor I will ever remarry. I know that's a strong statement, but I stand by it, and so does my husband.