In so many areas of life, it's not what happens, it's what you think about what happens. It's what you decide about what happens. A situation, a person, a relationship is what you decide it is. Two people can draw very different conclusions from the very same vantage point. One can see problems; the other can see possibilities. One can see burdens, the other, blessings. This is the power of perception and it can certainly make or break a marriage. How do you view your partner? Do you see uniqueness, strengths, virtues and attributes, or do you see faults, failures, shortcomings and imperfections? You can find both. The fact is that you see what what you look for AND what you focus on, you magnify.
In his book, "The Seven Principles for Making Marriage Work," John Gottman warns against an "if only" mindset. "If only your spouse were taller, richer, smarter, sexier, neater, nicer, your relationship would be great." "If only" is about what's missing in your partner or what you wish wasn't there. A focus like that will leave you dissatisfied and negative (and unlikely to see anything positive).
A warning sign in a relationship is when we convince ourselves that our partner is the problem. We fall into blame, criticism and the foolish impression that, if only your partner were more like you, everything would be alright.
So, here is the question: When you look at your partner, do you see differences or deficiencies? Seeing differences allows you to accept and even respect and appreciate your partner's unique characteristics and preferences for what they bring to your relationship. Healthy couples learn to empathize and accommodate one another.
Struggling couples don't see differences in their partner. They see deficiencies. They see things that need to be challenged at least and changed at worst. It's a formula for bitterness and resentment.
You didn't marry your clone. You wouldn't want to. So, try hard to talk about, understand better and respect what is different between you, rather than judge or belittle. Remember--differences, not deficiencies.