Marriage is hard work but it's good. It's good for many reasons but not the least of which is the fact that marriage is God's gift to us to teach us about the beautiful mystery of Christ and his church (Eph 5:32). It's very easy to forget this truth primarily because of the reality of the presence of sin. I know of no marriage that doesn't have conflict on some level, in some way, in various times and in various ways. But how we engage in the conflict is a reflection of the degree to which the gospel is taking root in our souls, affecting our hearts and minds to persevere in love no matter what happens.
In my counseling work, I offer couples a new angle on understanding why they face the problems they face. I summarize everything into one word: sin. Sin is the reason why they struggle with whatever it is that brings them to the counseling office.