You can choose either to have patience or to be short tempered. You can be forgiving or relentless in looking for shortcomings and failures. When we see marriage as an opportunity to acquire mitzvos, it takes on a new dimension. Just treating one's spouse with kindness and consideration brings with it great rewards, which will be felt for generations to come. Remind yourself of this repeatedly throughout the day, so that when you meet your spouse, you will be prepared for the challenge.
Some people are kind and polite away from home, but rude and unpleasant at home.
Their public actions are for the sake of display and are not motivated by true chesed. One must learn that the most appropriate place to practice chesed is at home, where you can do so much good and gain so much reward, if you only keep your eyes open to the many opportunities that arise. In this light, marriage is a gold mine. So many times during the day we can obtain mitzvos so easily, right in the midst of ordinary, mundane activities. When we understand this principle, our outlook on marriage can only be positive.