When genuine repentance is offered, practice speaking forgiveness explicitly and aloud: "I forgive you." Don’t default to, "It's okay" (it may not be okay) or "Don't worry about it" – but a clear, deliberate expression of forgiveness. This begins to train the heart to follow the words.

Agree together that you will not let the sun go down on unresolved anger (Ephesians 4:26). In practice, if a conflict arises too late or you are too emotional to resolve, agree to a specific time within 24-hours to return to it.

On a monthly basis, ask yourself individually:
"Is there anything I have said I forgave but am still holding onto?"

Bitterness is unforgiveness that went underground. Naming it – to God and, if appropriate, to your spouse – begins to release it.

Normalize meeting with a counselor, pastor, or mentor couple – not just during a crisis, but as a regular practice. Many reconciliation needs that have accumulated over the years could be addressed early on with a third-party perspective.