You know I asked this question once when my brother was going through his first divorce. My Dad, very wise in the Lord gave me this answer.
There is no such thing. Now, on that note, I believe God had my husband planned for me. There is a song I love. "I wonder what God was thinking, when He created you. I wonder if He knew everything I would need because He made all my dreams come true. When God made you, He must have been thinking about me."
Anyway, I also believe that we make bad choices. To explain my brother's situation...He had premarital sex and got his girlfriend pregnant. They decided to get married. Was she the one God had chosen...maybe not. But in any event, my brother made a choice to marry her. God is against divorce. That being said, when someone makes a choice on their own as my brother did, that person becomes part of God's plan for you. Not that anything is a surprise to God as He knows what we are going to do long before we ever do it.
If you are willing to pray and seek the Lord and work toward your marriage, it will be just what you make it..."a match made in heaven if you want to call it that." Even if my brother had married say the "girl God had planned for him," assuming that he did not in the first place. Marriage still takes work. There is no perfect marriage. When Lee and I were dating, I was told many times that there were not two more perfect people for each other than us. But that doesn't mean we don't argue or struggle sometimes. We have to work to make our marriage work.
I like these books, "The Power of a Praying Wife/Husband." This lady wanted a divorce, but God changed her heart through prayer and in time, her husbands heart was changed as well. They are still married many, many years later and are both Christians now.