A helpful thought here from Tim Keller-

The moment you marry someone, you and your spouse begin to change in profound ways, and you can't know ahead of time what those changes will be. So you don't know, you can't know, who your spouse will actually be in the future until you get there...

Over the years you will go through seasons in which you have to learn to love a person who you didn't marry, who is something of a stranger. You will have to make changes that you don't want to make, and so will your spouse. The journey may eventually take you into a strong, tender, joyful marriage. But it is not because you married the perfectly compatible person. That person doesn't exist.

- Tim Keller, The Meaning of Marriage

(HT: Vitamin Z)