Something I've read is that even if we are only 1% responsible for the struggles in our marriage, we are 100% responsible before God for our 1%. Someone has said that marriage is not a 50/50 proposition, but that each spouse must be giving 100%. Another has said that sometimes one spouse gives 60% and one gives 40%, then sometimes the percentages switch.
I found it so helpful, when I didn't know what else to do, to pray Psalm 51 outloud. It is David's prayer of repentance after Bathsheba.
Have mercy on me, O God, according to your unfailing love; according to your great compassion blot out my transgressions. Wash away all my iniquity and cleanse me from my sin. For I know my transgressions, and my sin is always before me. Against you, you only, have I sinned and done what is evil in your sight, so that you are proved right when you speak and justified when you judge. Surely I was sinful at birth, sinful from the time my mother conceived me. Surely you desire truth in the inner parts; you teach me wisdom in the inmost place. Cleanse me with hyssop, and I will be clean; wash me, and I will be whiter than snow. Let me hear joy and gladness; let the bones you have crushed rejoice. Hide your face from my sins and blot out all my iniquity. Create in me a pure heart, O God, and renew a steadfast spirit within me. Do not cast me from your presence or take your Holy Spirit from me. Restore to me the joy of your salvation and grant me a willing spirit, to sustain me. Then I will teach transgressors your ways, and sinners will turn back to you. Save me from bloodguilt, O God, the God who saves me, and my tongue will sing of your righteousness. O Lord, open my lips, and my mouth will declare your praise. You do not delight in sacrifice, or I would bring it; you do not take pleasure in burnt offerings. The sacrifices of God are a broken spirit; a broken and contrite heart, O God, you will not despise. In your good pleasure make Zion prosper; build up the walls of Jerusalem. Then there will be righteous sacrifices, whole burnt offerings to delight you; then bulls will be offered on your altar. ~ Psalm 51
Even if we haven't committed the sins of adultery and murder like David, who of us wouldn't want a cleaner heart before God, and who of us can totally clean our hearts without God's help?