There are some common things that people do to undermine the health of their marriage. One of the big ones is harboring an attitude of contempt toward your partner. This attitude, whether expressed explicitly or not, is one of the things you can indulge in that is most deadly for the longevity and happiness of your marriage.
Going hand in hand with this attitude is making negative interpretations of your partner. Doing this will practically guarantee defensiveness and negative behavior in return, fueling your negative interpretations. The key thing that helps one avoid these problems is to shift your focus away from thinking about what is wrong with your partner, to trying to identify which of your own communication behaviors are counterproductive, and which of your own wishes and associated feelings are at stake. If you want help learning how to do this, check out Empathy for yourself: Focusing.
It may help you to try to imagine (and to ask for) your partner’s hopes, dreams and expectations that may be different from yours. Give your partner the benefit of the doubt and assume that their hopes and dreams are legitimate.
It can also help to discover whether the two of you have legitimately different ways that you instinctively try to maintain emotional stability (e.g., some people use routine to keep from getting anxious, while others find this kills spontaneity). Another thing that might help you counter a tendency to feel contempt for your partner is to consider that they may be reacting reasonably to feeling dismissed by you. There are many more valuable things to learn about couple communication available at Maintaining Joint Empathy – For Couples and Close Relationships.